Composition for long-acting peptide analogs

ABSTRACT

The invention describes compositions of peptide analogs that are active in blood or cleavable in blood to release an active peptide. The peptide analogs have a general formula: A-(Cm) x -Peptide (SEQ ID NO: 76), wherein A is hydrophobic moiety or a metal binding moiety, e.g., a chemical group or moiety containing 1) an alkyl group having 6 to 36 carbon units, 2) a nitrilotriacetic acid group, 3) an imidodiacetic acid group, or 4) a moiety of formula (Z y His w ) p  (SEQ ID NO: 50), wherein Z is any amino acid residue other than histidine, His is histidine, y is an integer from 0-6; w is an integer from 1-6; and p is an integer from 1-6; wherein if A has alkyl group with 6 to 36 carbon units x is greater than 0; and Cm is a cleavable moiety consisting of glycine or alanine or lysine or arginine or N-Arginine or N-lysine, wherein x is an integer between 0-6 and N may be any amino acid or none. The peptide analogs are complexed with polymeric carrier to provide enhanced half-life.

CROSS-REFERENCE

This application claims priority as a continuation under 35 U.S.C. §120of U.S. patent application Ser. No. 12/184,186, filed Jul. 31, 2008,which claims priority under 35 U.S.C. §119(e) of U.S. ProvisionalApplication No. 60/953,789, filed Aug. 3, 2007. The contents of both areincorporated herein by reference in their entirety.

STATEMENT AS TO FEDERALLY SPONSORED RESEARCH

This invention was made in part with government support under 5 R43DK069727 awarded by the National Institute of Diabetes and Digestive andKidney Diseases (NIDDK). The U.S. Government may have certain rights insubject matter provided herein.

SEQUENCE LISTING

The instant application contains a Sequence Listing which has beensubmitted in ASCII format via EFS-Web and is hereby incorporated byreference in its entirety. Said ASCII copy, created on Apr. 22, 2011, isnamed 35227731.txt and is 39,926 bytes in size.

BACKGROUND OF THE INVENTION

The development of new formulations and delivery systems foradministration of physiologically active peptides and proteins and othertherapeutics and materials is driven by the need to provide thesepeptides or proteins or other materials to achieve the desirablephysiological effects. With respect to peptides and proteins, many ofthem must be delivered via systemic circulation. In addition, peptidesand proteins that have low molecular masses tend to have shortbiological half-lives due to their efficient removal from systemiccirculation via kidneys. For example, a fraction of these peptides andproteins can also be removed via reticulo-endothelial uptake due torecognition by monocyte/macrophages or as a result of opsonization bycomplement components. Many peptides and proteins can also lose theiractivity in vivo due to proteolysis (peptide bond cleavage).

In part to circumvent these undesirable effects, a drug delivery systemmay be used. There are several drug delivery strategies that can beuseful for peptide and protein delivery in vivo. First, a continuoussystemic infusion of drug via a pump can be employed. This strategy isproven efficient in clinical practice but may be impractical foroutpatients requiring high levels of mobility, associated disadvantagesof quality of life and potential intravenous (I.V.) line infections.Thus, there is a need for improved compositions and formulations for theadministration of peptides that have a prolonged half-life to reduce theneed for frequent and repeated administrations or infusions.

Cirrhosis of the liver is a common consequence of excessive alcoholconsumption or hepatitis leading to life-threatening complications. Inpatients with cirrhosis and type 1 hepatorenal syndrome (HRS),splanchnic vasodilation resulting from portal vein hypertension plays acritical role in the progression to renal failure. The use of splanchnicand systemic vasoconstrictors such as vasopressin agonists oralpha-1-adrenergic receptor agonists can improve renal function inpatients with type 1 HRS. Studies also suggest that vasoconstrictoradministration is a promising therapeutic approach targetingvasodilation involved in, but not limited to (1) renal failure in type 2HRS; (2) esophageal varices; (3) paracentesis-induced circulatorydysfunction; (4) arterial hypotension induced by byproducts of bacteria,(5) anesthesia-associated hypotension, (6) cardiac arrest, and (7)post-partum hemorrhage. Under these conditions a long actingvasoconstrictor such as long-acting vasopressin will be beneficial forthese patients.

HRS is characterized by renal failure in patients with advancedcirrhosis and liver failure, and severe sinusoidal portal hypertension.There are two types of HRS, type 1 and type 2. Type 1 is characterizedby rapid deterioration of renal function with doubling of serumcreatinine to greater than 2.5 mg/dL (221 uM) in less than 2 weeks withmedian survival of 1.7 weeks. Type 2 is characterized by stable orslowly progressive renal dysfunction with median survival of 6 months.The probability of developing HRS in cirrhosis patients with ascites is19% at 1 year and increases to 39% at 5 years.

Esophageal Variceal Hemorrhage (EVH) is a complication of portalhypertension resulting from cirrhosis. EVH accounts for 6-12% of upperGI bleeds (Longstreth G F, et al. Am J Gastroenterol 1995;90(2):206-210; Wilcox C M, et al. Southern Medical Journal 1999;92(1):44-50; Sorbi D, et al. Am J Gastroenterol 2003; 98(11):2424-2434).The treatment of EVH according to ACG Guidelines (1997) is endoscopictreatment (ligation or sclerotherapy) in combination with vasoactivetherapeutics; e.g., vasopressin or its analogs.

SUMMARY OF THE INVENTION

The present disclosure provides compositions of complexes containingbiologically active peptides, formulations and methods of use of suchcompositions. In part, the present invention is directed to peptidecomplexes for administration to a patient that are configured to deliverand prolong the half-life of biologically-active peptides and proteinsin vivo.

One embodiment of the invention relates to a group of novel long-actingvasopressin analogs, their formulation and methods of treatment usingthese compounds to increase perfusion to various organs in hypovolemicand hypotensive situation and increase the level of factor VIII andplasminogen activator in the blood. More particularly, the invention isconcerned with vasopressin and biologically-active polypeptidederivatives of vasopressin which have been modified by covalent bindingof binding moieties to produce long acting analogs of the polypeptidesthat are believed to function by slow release of an active vasopressinor vasopressin derivative. Furthermore, the modifications in thevasopressin analogs of the present invention allow the analogs to beloaded into a hydrophobic containing carrier polymer for slow release ofthe analogs into the blood and their activation into vasopressin. Inanother aspect of the invention the vasopressin analogs containsufficient hydrophobic chains to form micelle allowing for even sloweractivation and longer-sustained release or half-life. The disclosurealso provides modifications of the analogs of the present invention thatcan be loaded into metal chelate containing polymeric carriers for slowrelease of the analogs into the blood and, if needed, allows for theiractivation after release.

Another embodiment of the invention relates peptides with chelatinggroups or alkyl groups, such as fatty acids, attached to carboxyl oramino terminal of peptides, their formulation and methods of treatmentusing these peptides. In one particular example, the invention isconcerned with analogs of GLP-1 (7-36) and GLP-1 (7-37) where thecarboxyl terminal is modified with nitrilotriacetic acid orimidodiacetic acid that will allow GLP-1 to be anchored non-covalentlyto a carrier containing metal ion, preferably Zn or Cu. Furthermore, theGLP-1 analogs of the present invention allow the analogs to be loadedinto a hydrophobic- and metal ion-containing polymer for slow releaseinto the blood. The long acting GLP analogs are especially useful forthe treatment of diabetes and cardiovascular disease. Furthermore,modifications of the peptides at amino or carboxyl terminals byattaching nitrilotriacetic acid or imidodiacetic acid allow theresulting peptide analogs of the present invention to be loaded intometal chelate containing polymeric carriers for slow release of theanalogs into the blood and, if needed, allows for their activation byproteases after release.

Vasopressin agonists are used therapeutically to induce splanchnic andsystemic vasoconstriction, thereby restoring hemodynamic balance andincreasing organ perfusion. However the use of vasopressin is limiteddue to its short 24 minute half-life and its need to be administered byinfusion or repeated and frequent injections. Longer-acting syntheticvasopressin analogs are useful in conditions featuring low vasopressinsecretion, as well as for control of bleeding (in some forms of vonWillebrand disease), extreme cases of bedwetting by children andesophageal varices (Barett et al., Gastroenterology 1970; 58:926).Ideally, a very long acting vasopressin agonist administered once a daywill be useful in the prolonging the survival of patients waiting forliver transplantation compared to continuous infusion or twice dailyadministration. The present invention relates to vasopressin analog thatwill be slowly activated in the blood and can potentially beadministered once a day, once every two days, once every three to sixdays or even once a week. This would be ideal as a second line oftreatment for the management of septic shock patients not responding tohigh dose of inotropes, e.g., dopamine or norepinephrine. It had beenshown that vasopressin analogs are more effective than epinephrine inasystolic cardiac arrest (Wenzel V, et al. A Comparison of Vasopressinand Epinephrine for Out-of-Hospital Cardiopulmonary Resuscitation. NEngl J Med 2004; 350:105-13). While not all studies are in agreement, a2006 study of out-of hospital cardiac arrests has added to the evidencefor the superiority of vasopressin or its analogs in this situation(Crit. Care. 2006 February; 10(1):R13 (Crit. Care. 2006 February;10(1):R13). This effectiveness can be further enhanced if thevasopressin analogs are longer-acting than those that exist today.

Vasopressin analogs in the present invention can also be used fornon-liver disease-related disorders such as anesthesia-associatedhypotension, refractory septic shock, asystolic cardiac arrest,bronchoscopy-related bleeding, burns-grafting-associated bleeding,colonization of uterine cervix (for cervical neoplasia)-associatedbleeding, and labor-related blood loss.

One embodiment of the invention is a fatty acid containing analog of abiologically active peptide, which may or may not be biologically activeas an analog, that can be easily activated in biological fluid byremoval of fatty acid containing moiety by endogenous enzyme. The termpeptide as used herein means polymers of less than 100 amino acids.Further, the analogs of the present invention can optionally be loadedinto a polymeric carrier containing cores of a protective polymeric ornon-polymeric carrier with linked hydrophobic groups that allows forslow release of the peptide analogs in biological fluids for subsequentactivation or removal of the fatty acid containing moiety. An example ofa polymeric carrier comprising protective polymeric carrier containinghydrophobic groups is described in U.S. patent application Ser. No.11/613,183, which is hereby incorporated by reference. This loading canfurther slow down the activation or removal of the fatty acid containingmoiety or its degradation to provide a sustained level of peptideactivity in biological fluids over a longer period of time. In addition,the modification of peptide or its analogs with fatty acids allows formicelle formation that slows down the activation and degradation of theanalogs in biological fluids and can potentially slow down theactivation in blood. In another embodiment of the present invention, thepeptide can be modified to contain a chelating molecule to facilitateloading into the polymeric carrier with coordinately immobilized orchelated metal ion which will slow down the release of and subsequentactivation or degradation of the peptide in biological fluids. The termloading as used herein means reversible attachment of peptide to thecarrier including metal bridges as described in U.S. Pat. No. 7,138,105B2, which is hereby incorporated by reference.

We have found that fatty acid-containing analogs of vasopressin, asynthetic peptide previously used in the control of bleeding esophagealvarices, can be easily activated in serum. Further, the vasopressinanalogs of the present invention can be loaded into a protectivepolymeric nanocarrier containing hydrophobic groups. This loading canslow down the activation into active vasopressin to provide sustainlevel of vasopressin in biological fluids over a long period of time. Inaddition the modification of vasopressin analog, terlipressin, withfatty acids allows for micelle formation that slows down the activationof the analogs in biological fluids and can potentially slow down theactivation in blood.

The histidine-, iminodiacetic acid- or nitrilodiacetic acid-containinganalogs of vasopressin or other peptides can also be easily activated inbiological fluids by proteases, or they may be self-activating. Further,the vasopressin analogs of the present invention can be loaded into aprotective polymeric or non-polymeric nanocarrier containing chelatedmetals. This loading can slow down conversion of histidine containinganalog of vasopressin into active vasopressin and can provide asustained level of vasopressin in biological fluid over a long period oftime.

The present invention relates to peptide analogs having the generalformula: A-(Cm)_(x)-peptide (SEQ ID NO: 76) or peptide-(Cm)_(x)-A (SEQID NO: 77), wherein the left side of the peptide is N-terminal and theright side is C-terminal; Cm is Gly, Ala, Arg, Lys, a moiety of formula(N)_(q)-Arg, wherein N is any amino acid and q is 0 or 1, or a moiety offormula (N)_(q)-Lys, wherein N is any amino acid and q is 0 or 1, and xis an integer from 0-6; A can be any chemical group or moiety containingalkyl group having 6 to 36 carbons, a nitrilotriacetic acid group, animidodiacetic acid group, or a moiety of formula (Z_(y)His_(w))_(p) (SEQID NO: 50), wherein Z is an amino acid residue other than histidine, Hisis histidine, y is an integer from 0-6, w is an integer from 1-6, p isan integer from 1-6, and x is an integer from 2-6. The peptide can beany sequence or chain of 5-100 amino acids Amino acids in the chain canbe any combination of the 20 naturally occurring amino acids or theirderivatives.

The present invention also relates to a vasopressin analog having thegeneral formula: A-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-B-C-D (SEQ IDNO: 1) wherein A is chemical group or moiety containing alkyl group with3 to 36 carbon units, nitrilotriacetic acid group, imidodiacetic acidgroup, or (His)_(x) group (SEQ ID NO: 51), where x is an integer from2-6; Gly is Glycine; Cys is Cystine or Cysteine; Tyr is Tyrosine; Phe isPhenylalanine; Gln is Glutamine; Asn is Aspargine; Pro is praline; B isLysine or Arginine; C is Glycine or Alanine; D is NH₂ or H.

In another embodiment of above aforementioned composition, A is a groupcontaining a linear alkyl group with the formula CH₃(CH₂)_(n)—CO—,wherein n is an integer 4-34. In another embodiment of aboveaforementioned composition, A is a branched alkyl carbonyl group with6-36 carbon units. In another embodiment of above aforementionedcomposition, A is (His)_(x)- (SEQ ID NO: 51), wherein x is an integerfrom 2-6.

It is understood that in the above composition where A contains alkylgroup(s), the composition can form micelle that will slow down theactivation and degradation of vasopressin analogs in the absence of anypolymeric carrier.

The present invention also relates to the aforementioned composition,further comprising polymeric carrier with hydrophobic group(s) orpolymeric carrier with covalently linked metal binding domains andchelated metal. It is the object of the present invention to attach thehistidine portion, nitrilotriacetic acid, or imidodiacetic acid portionof the vasopressin analogs to the metals chelated by the metal bindingdomains of the polymeric carrier by coordination bonding between thehistidine, nitrilotriacetic acid, or imidodiacetic acid and the metalchelated by the polymeric carrier. It is also the object of the presentinvention to non-covalently attach the alkyl portion of the vasopressinanalogs to the hydrophobic portion of the polymeric carrier. Theseattachments will protect the analogs from rapid degradation in vivo butwill allow for the slow release of the vasopressin analogs into thecirculation for activation. Essentially the polymeric carrier will actas a reservoir for the vasopressin analogs which will release theanalogs depending on their dissociation constant (Kd) with the carrier.As the amount of unbound analogs gets used up by 1) protease thatactivates it, or 2) by its physiological receptors, more analogs will bereleased for further activation or utilization. As a result, a sustainedlevel of vasopressin will remain active in the blood for a longer periodof time.

In general, in one aspect compositions are provided. The compositionsinclude compounds of the general formula A-(Cm)_(x)-peptide (SEQ ID NO:76), wherein the peptide is a biologically active peptide having no morethan 100 amino acids; Cm is a Gly moiety, wherein x is an integer from0-6; or a Ala moiety, wherein x is an integer from 0-6; or a Arg moiety,wherein x is an integer from 0-6; or a Lys moiety, wherein x is aninteger from 0-6; or a moiety of formula (N)_(q)-Arg, wherein N is anyamino acid and q is 0 or 1 and x is an integer from 0-6; or a moiety offormula (N)_(q)-Lys, wherein N is any amino acid and q is 0 or 1 x is aninteger from 0-6; and A is an alkyl group having 6 to 36 carbons and xis an integer from 2-6; or a nitrilotriacetic acid moiety; animinodiacetic acid moiety; or a moiety of formula (Z_(y)His_(w))_(p)(SEQ ID NO: 50), wherein Z is an amino acid residue other thanhistidine, His is histidine, y is an integer from 0-6, w is an integerfrom 1-6, p is an integer from 1-6, and x is an integer from 2-6. In anexemplary embodiment, A is His₆ (SEQ ID NO: 52). In some aspects, thecompounds of the composition include a Cm wherein Cm is Gly andA-(Gly)_(x) (SEQ ID NO: 57) is attached to the peptide through an amidebond at the N-terminus. In one embodiment, Cm is Gly and A-(Gly)_(x)(SEQ ID NO: 57) is attached to the peptide through a side chain of anamino acid of the peptide. In another embodiment Cm is Gly andA-(Gly)_(x) (SEQ ID NO: 57) is attached to the peptide through an amidebond at the C-terminus. In another embodiment, the composition can havea general formula of A-(Cm)_(x)-peptide (SEQ ID NO: 78), wherein(Cm)_(x) is Gly-Gly-Gly-; A- is amide bonded to the amino terminus of-Gly-Gly-Gly-; and A-Gly-Gly-Gly- is amide bonded to any amino group ofthe peptide. In an example of the foregoing embodiment, the peptide is avasopressin analog having the general formulaCys-Tyr-Phe-Gln-Asn-Cys-Pro-B-C-D (SEQ ID NO: 53), wherein B is lysineor arginine; C is glycine or alanine; and D is NH₂ or H. In anotherexample of the foregoing embodiment, the peptide is GLP and A-(Cm)_(x)-is not attached to the N terminus of the peptide. The foregoingembodiments may also include compositions where A is a linear alkylcarbonyl group with formula CH₃(CH₂)_(n)—CO—; wherein n is an integerbetween 4-34, or n is 6 or 10 and Cm is Gly-Gly-Gly. In another exampleof the forgoing embodiments, A is a branched alkyl carbonyl group with6-36 carbon units attached through the carbon of the carbonyl group. Inone embodiment, the vasopressin analog isCH₃(CH₂)₆CO—OCH(CH₃)CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 37). In another embodiment, the vasopressin analog isHis-His-His-His-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 38).

In another aspect, the foregoing compositions further include apolymeric carrier with multiple alkyl chains of 6-36 carbon unitswherein the alkyl carbonyl groups of a plurality of peptide analogcompounds are non-covalently bound to the multiple alkyl chains of thepolymeric carrier by hydrophobic interaction. In another embodiment, theforegoing compositions further a include polymeric carrier withcovalently linked metal binding domains and chelated metal ions.

In another aspect, the compositions include a polymeric carriercomprising a polymeric core; a plurality of first hydrophobic groupscovalently bound to the polymeric core; a plurality of protective sidechains, wherein each protective side chain is covalently bound to thepolymeric core and has a molecular weight between about 400 and 20,000Daltons independent of the polymeric core weight; and a plurality ofpeptide analogs, each comprising a peptide covalently bound to a secondhydrophobic group, wherein said peptide analogs are non-covalently boundto the polymeric carrier through a hydrophobic interaction between thefirst hydrophobic groups and the second hydrophobic groups. In oneembodiment, the peptide is a vasopressin analog having the generalformula: Cys-Tyr-Phe-Gln-Asn-Cys-Pro-B-C-D (SEQ ID NO: 53), wherein B islysine or arginine, C is glycine or alanine, and D is NH₂ or H. Inembodiments of the foregoing, the hydrophobic group is a linear alkylcarbonyl group with formula CH₃(CH₂)_(n)—CO, wherein n is an integerbetween 4-34. In an exemplary embodiment of the foregoing, thevasopressin analog isCH₃(CH₂)₆CO—OCH(CH₃)CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 37). In another embodiment, the peptide of the foregoingcompositions is GLP. In an exemplary embodiment, the peptide analog ofthe foregoing compositions is GLP-Gly-Gly-Gly wherein Gly-Gly-Gly- isattached to the C terminus or a side chain of the peptide.

In another aspect, the compositions include a polymeric carriercomprising a polymeric core; a plurality of first chelating groupscovalently bound to the polymeric core, wherein the first chelatinggroups are coordinately bonded to a transition metal ion; a plurality offirst protective side chains, wherein each first protective side chainis covalently bound to the polymeric core and has a molecular weightbetween about 400 and 20,000 Daltons independent of the polymeric coreweight; and a plurality of peptide analogs, each comprising a peptidecovalently bound to a second chelating group, wherein said peptideanalogs are non-covalently bound to the polymeric carrier through acoordinate bond to the transition metal ion.

In one embodiment, the peptide is a vasopressin analog having thegeneral formula: Cys-Tyr-Phe-Gln-Asn-Cys-Pro-B-C-D (SEQ ID NO: 53),wherein B is lysine or arginine, C is glycine or alanine, and D is NH₂or H. In an exemplary embodiment, the vasopressin analog has the formulaHis-His-His-His-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 38). In another embodiment, the peptide of the foregoingcompositions is GLP. In an exemplary embodiment, the peptide analog ofthe foregoing compositions is GLP-Gly-Gly-Gly wherein Gly-Gly-Gly- isattached to the C terminus or a side chain of the peptide.

In another aspect of the invention, the foregoing compositions areformulated in a pharmaceutically acceptable carrier.

In yet another aspect, the invention provides methods of administeringthe foregoing compositions to a patient. In one embodiment, theinvention provides methods of administering the foregoing vasopressinanalogs to a patient in the treatment of hypovolemia, splanchnicvasodilation, systemic vasodilation, hypotension, esophageal varicealhemorrhage, hepatorenal syndrome, liver cirrhosis caused by alcohol orhepatitis, or sepsis.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1. The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus. This structure is also knownas terlipressin.

FIG. 2. The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus attached to lauric acid. Thisis also referred to as “C12TerA”. Using reverse phase HPLCchromatography in a Rainin (C18, 5 um, 4.6×250 mm), eluted with a lineargradient from water/0.1% TFA to 100% acetoinitrile/0.1% TFA over 20minutes at a flow rate of 1 ml/min, the C12TerA showed retention time of14.86 minutes as monitored at 215 nm and showed greater than 90% purity.Using mass spectrometer for total ion current, the purity was confirmedand a mass of 1409.5 Da was found corresponding to protonated peptide orthe molecular ion peak on mass spectroscopic analysis. This isconsistent with the theoretical molecular mass of 1410.4 Da whenprotonated. The absorption spectra showed a peak at 260 nm, which is 24times less than at 210 nm.

FIG. 3. The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus attached to lauric acid vialactic acid ester. This is also referred to as “C12TerE”. Using reversephase HPLC chromatography in a Rainin (C18, 5 m, 4.6×250 mm) eluted witha linear gradient from 30% aetonitrile/water/0.1% TFA to 90%acetoinitrile/water/0.1% TFA over 45 minutes at a flow rate of 1 ml/min,the C12TerE showed retention time of 20.91 minutes as monitored at 220nm and showed greater than 90% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 1481.6 Dalton wasfound corresponding to protonated peptide or the molecular ion peak onmass spectroscopic analysis. This is consistent with the theoreticalmolecular mass of 1482.5 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 18 times less than at 220 nm.

FIG. 4. The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus attached to octanoic acid. Thisis also referred to as “C8TerA”. Using reverse phase HPLC chromatographyin a Rainin (C18, 5 μm, 4.6×250 mm) eluted with a linear gradient from10% Acetonitrile/water/0.1% TFA to 70% acetoinitrile/water/0.1% TFA over45 minutes at a flow rate of 1 ml/min, the C8TerA showed retention timeof 23.17 minutes as monitored at 220 nm and showed greater than 90%purity. Using mass spectrometer for total ion current the purity wasconfirmed and a mass of 1354.0 Dalton was found corresponding toprotonated peptide or the molecular ion peak on mass spectroscopicanalysis. This is consistent with the theoretical molecular mass of1354.4 Dalton when protonated. The absorption spectra showed a peak at260 nm which is about 25 times less than at 210 nm.

FIG. 5. The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus attached to octanoic acid vialactic acid ester. This is also referred to as “C8TerE”. Using reversephase HPLC chromatography in a Rainin (C18, 5 μm, 4.6×250 mm) elutedwith a linear gradient from 10% acetonitrile/water/0.1% TFA to 70%acetoinitrile/water/0.1% TFA over 45 minutes at a flow rate of 1 ml/min,the C8TerE showed retention time of 27.32 minutes as monitored at 220 nmand showed greater than 95% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 1425.7 Dalton wasfound corresponding to protonated peptide or the molecular ion peak onmass spectroscopic analysis. This is consistent with the theoreticalmolecular mass of 1426.5 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 40 times less than at 210 nm.

FIG. 6. The figure depicts a chemical structure of lysine vasopressinwith three glycine residues at the N-terminus attached to threeHistidine residues. This is also referred to as “His3Ter”. Using reversephase HPLC chromatography in a Supelco (C18, 5 μm, 4.6×250 mm) elutedwith a linear gradient from 0% acetonitrile/water/0.1% TFA to 60%acetoinitrile/water/0.1% TFA over 45 minutes at a flow rate of 1 ml/min,the His3Ter showed retention time of 15.47 minutes as monitored at 220nm and showed greater than 95% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 1639.8 Dalton wasfound corresponding to protonated peptide or the molecular ion peak onmass spectroscopic analysis. This is consistent with the theoreticalmolecular mass of 1639.1 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 40 times less than at 210 nm.

FIG. 7. The figure depicts a chemical structure of lysine vasopressinwith three glycine residues at the N-terminus attached to six Histidineresidues (SEQ ID NO: 52). This is also referred to as “His6Ter” (“His6”disclosed as SEQ ID NO: 52). Using reverse phase HPLC chromatography ina Vydac (C18, 5 μm, 4.6×250 mm) eluted with a linear gradient from 0%acetonitrile/water/0.1% TFA to 100% acetoinitrile/water/0.1% TFA over 45minutes at a flow rate of 1 ml/min, the His6Ter (“His6” disclosed as SEQID NO: 52) showed retention time of 18.81 minutes as monitored at 220 nmand showed greater than 95% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 2051.3 Dalton wasfound corresponding to protonated peptide or the molecular ion peak onmass spectroscopic analysis. This is consistent with the theoreticalmolecular mass of 2051.1 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 42 times less than at 220 nm.

FIG. 8. The figure depicts a chemical structure of arginine vasopressinwith three glycine residues at the N-terminus attached to threeHistidine residues. This is also referred to as “His3Vas”. Using reversephase HPLC chromatography in a Rainin (C18, 5 μm, 4.6×250 mm) elutedwith a linear gradient from 0% acetonitrile/water/0.1% TFA to 60%acetoinitrile/water/0.1% TFA over 45 minutes at a flow rate of 1 ml/min,the His3Vas showed retention time of 18,45 minutes as monitored at 215nm and showed greater than 95% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 1668 Dalton was foundcorresponding to protonated peptide or the molecular ion peak on massspectroscopic analysis. This is consistent with the theoreticalmolecular mass of 1667.9 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 38 times less than at 210 nm.

FIG. 9. The figure depicts a chemical structure of arginine vasopressinwith three glycine residues at the N-terminus attached to six histidineresidues (SEQ ID NO: 52). This is also referred to as “His6Vas” (“His6”disclosed as SEQ ID NO: 52). Using reverse phase HPLC chromatography ina Supelco (C18, 5 μm, 4.6×250 mm) eluted with a linear gradient from 0%acetonitrile/water/0.1% TFA to 60% acetoinitrile/water/0.1% TFA over 45minutes at a flow rate of 1 ml/min, the His6Vas (“His6” disclosed as SEQID NO: 52) showed retention time of 17.27 minutes as monitored at 220 nmand showed greater than 95% purity. Using mass spectrometer for totalion current the purity was confirmed and a mass of 2080.5 Dalton wasfound corresponding to protonated peptide or the molecular ion peak onmass spectroscopic analysis. This is consistent with the theoreticalmolecular mass of 2079.3 Dalton when protonated. The absorption spectrashowed a peak at 260 nm, which is about 48 times less than at 210 nm.

FIG. 10. The figure depicts a schematic cross section of the micellethat forms from vasopressin analogs containing fatty chain. The darkheavy line is the hydrophobic chains while the light line represent thevasopressin with disulfide bonds. The cleavage sites shown in FIGS. 1 to5 are hidden from the surface of the micelle, and in this figure is atthe junction of light and heavy line.

FIG. 11. This figure shows the ability of terlipressin and othervasopressin analog to be activated by serum after 2-hour incubation inhuman serum. The Y-axis is relative fluorescence units in humanumbilical chord cells loaded with fura-2 in 96-well plate. Thefluorescence is proportional to the calcium in cells cytoplasm.Vasopressin causes calcium influx into the cells cytoplasm causing anincrease in fluorescence. Various vasopressin analogs are incubated withhuman serum for 2 hours and applied to cells in culture. Fluorescencewas measured at three second intervals for one minute. as shown. Afterapplication, those samples that get activated by serum cause calciuminflux and hence increase in fluorescence.

FIG. 12: All figures show 20 repeats of Fura-2 fluorescence as afunction of time in seconds on the x-axis. The y-axis shows fluorescenceintensity in relative fluorescence units [RFU]. After the first 4 datatime points, the drugs are injected into the tissue culture well andfluorescence measurement is continued for 48 more seconds. Fura-2fluorescence intensifies as intra-cellular Ca²⁺ concentration rise inresponse to a stimulus. Terlipressin is only fully active when injectedin the presence of serum since, as being an analogue, a short sequenceof amino acids needs to be cut off to leave fully active vasopressin.This step is very fast or the enzyme performing this step is active onice as the addition of human serum increases terlipressin activitysignificantly without pre-incubation at 37° C. Terlipressin loses itsactivity quickly due to degradation with increasing incubation time inserum. Because of endogenous growth factors contained in human serum,human serum by itself produces a measurable Ca-influx signal. Activityof the drugs therefore needs to exceed the human serum signal. TheC8TerA, C12TerA and C12TerE derivatives of terlipressin are similarlyactive but are protected for up to 4 h from degradation in serum.

FIG. 13: Results from the method of FIG. 12 showing terlipressin andderivatives in PBS.

FIG. 14: Results from the method of FIG. 12 showing teripressin in humanserum for varying intervals.

FIG. 15: Results from the method of FIG. 12 showing C8TerA analog inhuman serum for varying intervals.

FIG. 16: Results from the method of FIG. 12 showing C12TerA analog inhuman serum for varying intervals.

FIG. 17: This figure is a Scatchard plot showing the binding of C12TerAto polymeric carrier containing a hydrophobic group disclosed in U.S.patent application Ser. No. 11/613,183, which is hereby incorporated byreference. The carrier also referred to as PGC-HC18 or 20PLPEG555-C18 ismade up of polylysine of 15-30 kDa where 55% of the amino group iscovalently modified to contain 5 kDa methoxypolyethylene glycol attachedby through succinate linker and the remaining 45% of the amino group isamide bonded to stearic acid carboxyl group all disclosed in U.S. patentapplication Ser. No. 11/613,183. Two hundred fifty μl solutions ofcarrier (2.5 mg/tube) were mixed with 0.20, 0.15, 0.10, 0.075, 0.050,and 0.025 mg of C12TerA. Sample was made up to 150 μl PBS and incubatedovernight. The bound from 75 μl was eluted from Bio-spin-P30. The voidvolume containing loaded carrier was unloaded by filtration through 100kDa MWCO filter after addition of 75 μl acetonitrile, to release load.The filtrate containing bound C12TerA was quantified by HPLC. Acontrolled passed through the same filter in 50% acetonitrile was usedas a reference for the total C12TerA in each tube, allowing for thecalculation of Free C12TerA in the original incubation mixture. C12-TerAelutes at 2.4 minutes. A gradient of 25-99% acetonitrile from 1-6minutes at a flow rate of 1.5 ml/min was used. The column was Mercury MS20×4 mm; 2 um; C12 from Phenomenex. Although the Scatchard plot is notcompletely linear, an average Kd of 1-5 μM can be estimated, indicatinga strong interaction of C12TerA with the carrier containing thehydrophobic group, which is sufficient to prolong the biologicalhalf-life of the C12TerA and delay its rapid activation and degradation.It should be noted that some C12TerA can form micelle and may be countedas bound due to the analytical techniques used.

FIG. 18: The graph shows the bound and Free C12TerA in the presence of10 mg/ml PGC-HC18 or 20PLPEG555-C18. It should be noted that most of theC12TerA is bound to the carrier containing hydrophobic group, which issufficient to prolong the biological half-life of the C12TerA and delayits rapid activation and degradation.

FIG. 19: The figure depicts a chemical structure of vasopressin withthree glycine residues at the N-terminus attached to one of the carboxylgroup of nitrilotriacetic acid. This is also referred to as “NTA-Ter”.This can also be looked at as vasopressin with four glycine residueswhere the N-terminus is attached to two carboxymethyl groups.

FIG. 20: The figure depicts a chemical structure of peptide in generalwith nitrilotriacetic acid derivative [N′,N′,bis(carboxymethyl)-lysine]attached to the carboxyl terminal of peptide that allows the peptide tohave nitrilotriacetic acid residue. In one particular embodiment, thepeptide can have sequence of:

His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg(SEQ ID NO: 2); orHis-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly(SEQ ID NO: 3); orHis-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly(SEQ ID NO: 4); or

His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-Gly(SEQ ID NO: 5). The three letter codes are the amino acidrepresentations known in the art of peptides.

FIG. 21: The figure depicts a chemical structure of peptide in generalwith iminodiacetic acid attached to carboxyl terminal of peptide thatallows the peptide to have iminodiacetic acid residue. In one particularembodiment, the peptide can have sequence of:

His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ileu-Ala-Trp-Leu-Val-Lys-Gly-Arg(SEQ ID NO: 2); orHis-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ileu-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly(SEQ ID NO: 3); orHis-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ileu-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly(SEQ ID NO: 4); or

His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ileu-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-Gly(SEQ ID NO: 5). The three letter codes are the amino acidrepresentations known in the art of peptides.

FIG. 22: The figure depicts a chemical structure of peptide in generalwith nitrilotriacetic acid attached to the amino terminus or N-terminusof peptide that allows the peptide to have an iminodiacetic acidresidue. This is another embodiment of the present invention.

FIG. 23: This is a graph showing the bound and Free His6Ter (“His6”disclosed as SEQ ID NO: 52) in the presence of 10 mg/ml40PLPEG537-Zn-chelate. The 40PLPEG537-Zn-chelate has a 40 kDa polylysinebackbone with 37% of the lysine epsilon amino groups attached to 5 kDapolyethyleneglycol and the remaining 63% attached to Zn ion chelate, asdescribed in U.S. Pat. No. 7,138,105. The percent loading in the x-axisrepresent the amount of His6Ter (“His6” disclosed as SEQ ID NO: 52) as apercent of 10 mg/ml carrier. It should be noted that most of the His6Ter(“His6” disclosed as SEQ ID NO: 52) is bound to the carrier containingchelated zinc which is sufficient to prolong the biological efficacy ofthe His6Ter (“His6” disclosed as SEQ ID NO: 52). Several aliquots ofcarriers (2.5 mg carrier/tube) were mixed with 0.25, 0.20, 0.15, 0.10,0.075, 0.050, and 0.025 mg of His6Ter (“His6” disclosed as SEQ ID NO:52) and made up to 250 μl PBS and incubated overnight. To separate boundand free, the solution was filtered using 100 kDa molecular weightcut-of cellulose filter (Microcon Ultracel YM-100 from Millipore) bycentrifugation at 12,000×g for 10 minutes. The His6Ter (“His6” disclosedas SEQ ID NO: 52) in the filtrate was quantified by reverse phase HPLCusing synergimax (20×4 mm) with a gradient of 0-50% B (A is 5%acetonitrile with 0.1% TFA and B is 100% acetonitrile with 0.1% TFA)from 1-5 minutes at flow rate of 1.5 minutes. His6Ter (“His6” disclosedas SEQ ID NO: 52) comes out at 3.1 minutes. Free or unbound His6Ter(“His6” disclosed as SEQ ID NO: 52) was expressed as area under thecurve (AUC; y-axis). Controls without the carrier were passed throughthe same filter was and quantified similarly and used as a reference forthe total His6Ter (“His6” disclosed as SEQ ID NO: 52) from which freecan be subtracted to calculate the bound.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure provides compositions of biologically activepeptide complexes, formulations and methods of use of such compositionsfor the treatment of patients. The subject compositions, and methods ofmaking and using the same, may achieve a number of desirable results andfeatures. In one aspect, the present invention is directed to complexesof peptide analogs and polymeric carrier molecules that are configuredto deliver, release and/or prolong the half-life of biologically-activepeptides in a controlled fashion after administration to a patient. Inanother aspect, the present invention is directed to complexes ofpeptide analogs and polymeric carrier molecules that stabilize thepeptides to create formulations suitable for administration to apatient. The present disclosure provides peptides with covalentlyattached binding moieties of hydrophobic and/or metal binding groups(“peptide analogs”) that can reversibly bind to polymeric carriercontaining cores of hydrophobic polymeric carrier or polymeric carrierwith covalently linked metal binding domains and chelated metal to formcomplexes suitable for administration to a patient. The presentdisclosure also provides peptides with alkyl groups that can formmicelle or liposomes with or without cores of hydrophobic polymericcarrier. By way of a further embodiment, the peptide may optionally becovalently attached to hydrophobic or metal binding groups by acleavable linker moiety that can be cleaved by host proteases inbiological fluids or tissues, permitting the controlled and/or sustainedrelease of active peptide from the delivery complex.

U.S. Pat. No. 7,138,105 and United States patent publications2005-0260259, 2007-0141145 and 2008-0015263 describe drug polymericcarrier molecules that reversibly bind hydrophobic and metal bindingmolecules, such as peptides. These polymeric carrier molecules caninclude a polymeric core (e.g., a backbone), such as a polyamino acid,such as polylysine. Protective groups, such as polyethylene glycol canbe attached to the core. Also attached to the core are binding moietiesthat bind the molecule to be delivered. In certain embodiments, thebinding moieties bind molecules with hydrophobic groups. In this case,the binding moiety can be a hydrophobic group such as an alkyl group.Alternatively, the binding moiety binds with molecules that, themselves,bind metals. Such binding moieties include metal binding groups, such aschelating groups, bound to a metal, such as a transition metal (e.g.,Zn, Ni, Cu etc.).

I. Peptide Analog Compositions

This invention provides peptides that have been modified to includebinding moieties, such as hydrophobic groups or metal binding groups,through which the peptides can bind to the polymeric carrier molecules.Modifications can include hydrophobic moieties or metal binding groupsto create the peptide analogs of the invention. For example, ahydrophobic group can be an alkyl having 6-36 carbon atoms. A metalbinding group can be, for example, a His tag (e.g., His₆ (SEQ ID NO:52)). In certain embodiments, the binding moiety is attached directly tothe peptide to be delivered. In other embodiments, the binding moiety isattached to the peptide through a cleavable moiety, including sequencesof amino acids such as Gly-Gly-Gly and other amino acid sequencessusceptible to cleavage, as described more fully below. Thus, for thepurpose of the present invention, “peptide analog” means a peptide witha covalently bound binding moiety, as well as a peptide with acovalently bound cleavable moiety and a covalently bound binding moiety.Cleavage of the cleavable moiety in the body releases the peptide fromthe polymeric carrier. Thus, peptide compositions of the invention havethe general formula: Binding moiety—Optional cleavable moiety—Peptide,wherein the Binding moiety and Optional cleavable moiety can be bound,e.g., covalently, to the peptide at any appropriate location on thepeptide. The cleavable moiety finds use when the binding moietyinterferes with the biological activity of peptides.

Accordingly, this invention also provides peptide complexes between apolymeric carrier and a modified peptide of this invention in which themodified peptide is reversibly bound to the polymeric carrier throughhydrophobic attraction between alkyl groups of the modified peptide andpolymeric carrier, or a metal ion binding interaction between a metalbinding group of the modified peptide and metal binding groups andassociated metal ions of the polymeric carrier.

A. Peptides

For the purpose of the present invention, “peptide” means biologicallyactive polyamino acids ranging from 5 to 100 amino acids. In the past,polyamino acids larger than 51 amino acids were termed proteins while 51amino acid and smaller were termed peptides. The distinction betweenprotein and peptide is only a matter of size. The synthesis of longerpolyamino acids such as proteins has been challenging in the past due tosome technology limitations of peptide synthesizers. This difficultyresulted in the distinction between peptide and proteins. Theimprovement in peptide synthesis technology, however, now allows forlonger polypeptides up to 100 amino acids to be synthesized. It is alsothe intention of the present invention to include in the definition ofpeptide those polypeptides containing 5 to 100 amino acids since thetechnology now allows for the synthesis of those peptides in automatedpeptide synthesizer, making the old definition of peptide broader. Mostlarge proteins are still made recombinant methods in biological systemswhile peptides are made using peptide synthesizers. The addition ofalkyl groups, histidine, nitrilotriacetic acid, or iminodiacetic acid toa peptide can be easily done using a peptide synthesizer during peptidesynthesis. For recombinant proteins, these alkyl groups,nitrilotriacetic acid, or iminodiacetic acid may be introduced in matureproteins but with limited reaction predictability from protein toprotein. “Peptide” for the purpose of the present invention does notinclude homopolymers of amino acid such as polylysine, polyglutamic acidas they are not biologically active. The term “biologically active” forthe purpose of the present invention means the peptide can bind to acellular receptor that can send message inside the cell through a secondmessenger system that then causes a biological response. These are thepeptides/proteins that when modified as outlined in the instantspecification are the peptide of the present invention.

The biologically active peptides suitable for use in the presentinvention include peptides that by themselves are susceptible toenzymatic cleavage in biological fluids such as plasma or are otherwisecleared by the body such that they have a short half-life. The presentdisclosure provides compositions containing peptides with biologicalactivity that are suitable for treating a patient, such as vasopressin,terlipressin, glucagon like peptide (GLP), or analogs thereof. Othernon-limiting examples of peptides include, but are not limited to leptinfragment, gastric inhibitory polypeptide (GIP), epidermal growth factor(EGF) receptor ligand, EGF, transforming growth factor alpha(TGF-alpha), gastrin/cholecystokinin receptor ligand, gastrin,cholecystokinin, lysostaphin, interferon, interferon gamma, interferonbeta, interferon alpha, interleukin-1, interleukin-2, interleukin-4,interleukin-6, interleukin-8, interleukin-10, interleukin-12, tumornecrosis factor, tumor necrosis factor alpha, tumor necrosis factorbeta, auristatin, nisin, insulin, insulin-like growth factor, growthhormone, nerve growth factor, brain-derived neurotrophic factor,endostatin, angiostatin, trombospondin, urokinase, streptokinase, bloodclotting factor VII, blood clotting factor VIII, granulucyte-macrophagecolony-stimulating factor (GM-CSF), granulucyte colony-stimulatingfactor (G-CSF), thrombopoetin, calcitonin, parathyroid hormone (PTH) andits fragments, erythropoietin, atrial natriuretic factor, somatostatin,adrenocorticotropin, gonadotropin releasing hormone,leutinizing-hormone-releasing-hormone, follicle stimulating hormone,glucocerebrosidase, thrombopoietin, filgrastim, prostaglandins,epoprostenol, prostacyclin, desmopressin, or vasoactive intestinalpeptide (VIP).

The term “derivative” as used herein refers to a compound whose corestructure is the same as, or closely resembles that of, a parentcompound, but which has a chemical or physical modification, such as adifferent or additional groups. The term “derivative” includesco-polymers of parent compounds that can be linked to other atoms ormolecules. The term “derivative” also includes peptides with at least50% sequence identity with the parent peptide. The term “derivative”also include a peptide with additional groups attached to it, such asfatty acids and/or additional amino acids, but does not include bindingmoieties or cleavable moieties as they are defined herein. Vasopressinas use herein includes its derivatives such as terlipressin and othervariations thereof. Glucagon like peptide (GLP) as used herein includesGLP and its derivatives such as GLP-1 (7-36), GLP-1 (7-37), andexenatide and other variation thereof. For clarity of the specification,a linear peptide, also referred to as polypeptide or polyamino acid, hasa N-terminus and a C-terminus. The N-terminus refers to the alpha aminogroup of the terminal amino acid that is not used to form a peptidebond. The C-terminus refers to the alpha carboxyl group of the terminalamino acids that is not used to form a peptide bond. The N-terminus andC-terminus of a peptide is not in the R-group (known in the art) of anyamino acid that made up the peptide. Alkyl group for the purpose of thisinvention is a chemical group that is made up of only carbon andhydrogen. The preferred alkyl group in this invention contains 6 to 36carbon units with their covalently linked hydrogen atoms.

Peptide analogs can be generated using standard techniques of peptidechemistry and can be assessed for activity either before or afterincubation in serum. Particularly preferred peptides analogs of theinvention are those peptides containing 1) an alkyl group of 6-36 carbonunits at the N- or C-terminus of a linear peptide; or 2) iminodiaceticacid, which may or may not be a portion of nitrilotriacetic acid. Theanalogs can have a general formula: A-(Gly)_(x)-peptide (SEQ ID NO: 54)or peptide-(Gly)_(x)-A (SEQ ID NO: 55), wherein the left side of thepeptide is N-terminal and the right side is C-terminal; Gly is Glycine;where x is an integer from 0-5; A can be any chemical group or moietycontaining an alkyl group with 8 to 36 carbon units, a nitrilotriaceticacid group, a imidodiacetic acid group, or (His)_(y) (SEQ ID NO: 51);where y is an integer from 2-6. The peptide can be any sequence or chainof 5-100 amino acids. The amino acids can be any of the 20 naturallyoccurring amino acids or their derivatives. The attachment of A to thepeptide may involve simple linker group such as lactate or glycine.Lactate is especially important if we want to attach the alkyl groupusing an ester bond to the amino terminus of a peptide. To attach analkyl group to the carboxyl terminus of a peptide by amide bond, anamino-alkyl group will be used with the general formula CH₃(CH)_(n)—NH—;where n=5-34.

Analogs of peptides exemplified by vasopressin can be generated usingstandard techniques of peptide chemistry and can be assessed for calciuminflux activity before and after incubation in serum, all according tothe guidance provided herein. Preferred analogs of the invention arethose based upon the sequence of vasopressin, as follows:

A-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-B-C-D (SEQ ID NO: 56)

wherein:

-   -   A is selected groups containing alkyl group with 3 to 36 carbon        units, nitrilotriacetic acid, imidodiacetic acid or        (Z_(x)His_(y))_(p) (SEQ ID NO: 50); where Z is an amino acid        residue, His is histidine, x is an integer from 0-6; y is an        integer from 1-6; and p is an integer from 1-6;        -   Gly is Glycine        -   Cys is Cystine or Cysteine        -   Tyr is Tyrosine        -   Phe is Phenylalanine        -   Gln is Glutamine        -   Asn is Aspargine        -   Pro is proline        -   B is Lysine or Arginine        -   C is Glycine or Alanine        -   D is NH₂ or H        -   A-Gly-Gly-Gly- subunit is covalently attached to any            available amino group of the peptide by an amide bond.

Many of the protected amino acid residues useful in synthesizing thepreferred compounds of this invention are commercially available frommany amino acid suppliers. Furthermore, all the peptide analogs that arethe subject of the present invention can be synthesized by outsidecustom peptide providers such as Anaspec, San Jose Calif. USA,Polypeptide laboratories, Torrance, Calif., or ChemPep Inc, Miami, Fla.Synthesis of peptides according to the specification disclosed in thisapplication can easily be done by those skilled in the art andpreferably done using solid phase synthesis, especially if themodification is at a terminal residue of the peptides. For peptide withnitrilotriacetic acid at the carboxyl terminal (FIG. 20), thenitrilotriacetic acid derivative such as[N′,N′,bis(carboxymethyl)-lysine] that is protected at the N-terminal(by Fmoc or Boc, as known in the art) is first immobilized or conjugatedwith the resin where the remaining unreacted carboxyl group can beprotected if desired. The activated carboxyl group of the protectedincoming amino acid will then be conjugated to the amino group ofimmobilized N′,N′,bis(carboxymethyl)-lysine after Fmoc or Boc removaland the synthesis continues as normal solid phase peptide synthesis. Thecleavage from the resin, deprotection and purification is similar toconventional peptide synthesis with an extra option in the purificationstep of using metal affinity chromatography to purify. For peptide withiminodiacetic acid at the carboxyl terminus (FIG. 21), the iminodiaceticacid is first N-protected by Fmoc or Boc and then immobilized orconjugated with the resin through its carboxyl group and the secondunreacted carboxyl group can be protected if desired. The incomingactivated carboxyl group of the protected amino acid will then beconjugated to the secondary amino group of immobilized iminodiaceticacid (after Fmoc or Boc removal or deprotection) and the synthesiscontinues as normal solid phase peptide synthesis. For peptide withiminodiacetic acid at the amino terminus (FIGS. 19 and 22), thesynthesis continues as normal solid phase peptide synthesis and at thelast amino acid residue, activated nitrilotriacetic acid is conjugatedto the amino terminus of the growing chain. The activation ofnitrilotriacetic acid can be limited to one carboxyl pernitrilotriacetic acid, however this is not necessary from our experienceas excess of fully activated and N-protected nitrilotriacetic acidreacts only to one terminal amino group. The cleavage from the resin,deprotection and purification is similar to conventional peptidesynthesis with an extra option in the purification step of using metalaffinity chromatography to purify.

Once the desired analogs of peptides has been synthesized, cleaved fromthe resin and fully deprotected, the peptide is then purified to ensurethe recovery of a single oligopeptide having the selected amino acidsequence with the desired functional group. Purification can be achievedusing any of the standard approaches, which include reversed-phasehigh-pressure liquid chromatography (RP-HPLC) on alkylated silicacolumns, e.g. C₄₋₁₈ silica. Such column fractionation is generallyaccomplished by running linear gradients, e.g., 10-90%, of increasing %organic solvent, e.g., acetonitrile, in aqueous buffer, usuallycontaining a small amount (e-g., 0.1%) of pairing agent such as TFA orTEA. Alternatively, ion-exchange HPLC can be employed to separatepeptide species on the basis of their charge characteristics. Columnfractions are collected, and those containing peptide of thedesired/required purity are optionally pooled with the guide of TandemMass spectrometry detector. In one embodiment of the invention, thevasopressin peptide is then treated in the established manner toexchange the cleaving acid (e.g., TFA) with a pharmaceuticallyacceptable acid anion and to allow intra-molecular disulfide bridgeformation in dilute solution under a suitable oxidizing agent. Thisintra-molecular disulfide bridge formation can be confirmed by HPLC/MSanalysis.

B. Binding Moieties

The present disclosure provides binding moieties of hydrophobic or metalbinding groups that can be attached to the peptides and the polymericcarrier molecules of the embodiments that permit reversible binding topolymeric carrier to form the peptide complexes.

1. Hydrophobic Groups

In one aspect, the binding moiety of the modified peptide is ahydrophobic group, e.g., an alkyl group of 6 to 36 carbon units. Suchhydrophobic groups can non-covalently bind to hydrophobic groups in acarrier molecule. In one embodiment, the alkyl group of the bindingmoiety is a linear alkyl carbonyl group having a formulaCH₃(CH₂)_(n)—CO—, where n is an integer between 4-34, or a correspondingamino-alkyl group with 6 to 36 carbon units wherein the respective alkylgroups can be attached to the N- or C-terminus of the peptide or to aside chain of an amino acid of the peptide. In another embodiment, thealkyl group of the binding moiety is a branched alkyl carbonyl group ora branched amino-alkyl group with 6-36 carbon units attached,respectively, to the N- or C-terminus of the peptide or to a side chainof an amino acid of the peptide. The hydrophobic groups can also be ringcompounds of 6-36 carbon units.

2. Metal Binding Groups

In another aspect, the present disclosure provides binding moieties witha metal binding domain, such as those disclosed in U.S. patentapplication Ser. No. 11/112,879, which is incorporated herein byreference, in its entirety.

The metal binding moiety can be any conformational arrangement ofseveral chemical groups that is capable of forming a complex between themetal ion and the chemical groups by coordinate bonds. In certainembodiments, the metal binding moiety is a chelating group. Chelatinggroups posses a pair of unpaired electrons that are available forcoordinate bonding with a metal ion. Bidentate-, tridentate- andtetradentate chelating groups are well known in the art.

In one embodiment, a plurality of metal binding moieties with chelatedmetal ion are covalently attached to the core polymer of the polymericcarrier, a metal binding moiety is covalently to the peptide which formsa reversible coordinate bond to the metal ion. In general, the metalbinding domains of the metal binding moieties used in the presentinvention contain a Lewis base fragment that is contemplated toencompass numerous chemical moieties having a variety of structural,chemical and other characteristics capable of forming coordination bondswith a metal ion. The types of functional groups capable of formingcoordinate complexes with metal ions are known to those of skill in theart. For example, such moieties will generally include functional groupscapable of interaction with a metal center, e.g., heteroatoms such asnitrogen, oxygen, sulfur, and phosphorus. Metal cations are almostalways Lewis acidic and are therefore able to bind various moieties thatmay serve as Lewis bases. In preferred embodiments, the metal chelateions include, but are not limited to, Zn²⁺, Ni²⁺, Co²⁺, Fe²⁺, Mn²⁺, andCu²⁺.

In general, a moiety serving as a Lewis base will be a strongly acidicgroup, e.g., with a pKa less than about 7, and more preferably less than5, which may produce a conjugate base that, under the appropriateconditions, is a strong enough Lewis base to donate an electron pair toa metal ion to form a coordinate bond. The degree of this Lewisacid-to-Lewis base interaction is a function not only of the particularmetal ion, but also of the coordinating moiety itself, because thelatter may vary in the degree of basicity as well as in size and stericaccessibility. Exemplary Lewis basic moieties which may be included inthe metal binding domain include: amines (primary, secondary, andtertiary) and aromatic amines, amino groups, amido groups, nitro groups,nitroso groups, amino alcohols, nitriles, imino groups, isonitriles,cyanates, isocyanates, phosphates, phosphonates, phosphites, phosphines,phosphine oxides, phosphorothioates, phosphoramidates, phosphonamidites,hydroxyls, carbonyls (e.g., carboxyl, ester and formyl groups),aldehydes, ketones, ethers, carbamoyl groups, thiols, sulfides,thiocarbonyls (e.g., thiolcarboxyl, thiolester and thiolformyl groups),thioethers, mercaptans, sulfonic acids, sulfoxides, sulfates,sulfonates, sulfones, sulfonamides, sulfamoyls and sulfinyls.

Illustrative of suitable metal binding domains include those chemicalmoieties containing at least one Lewis basic nitrogen, sulfur,phosphorous or oxygen atom or a combination of such nitrogen, sulfur,phosphorous and oxygen atoms. The carbon atoms of such moiety may bepart of an aliphatic, cycloaliphatic or aromatic moiety. In addition tothe organic Lewis base functionality, such moieties may also containother atoms and/or groups as substituents, such as alkyl, aryl andhalogen substituents. Preferred binding moieties are nitrilotriaceticacid and iminodiacetic acid groups, or his tags that consist of two tosix linked histidine residues (SEQ ID NO: 51).

In one embodiment, the metal binding moiety of the peptide analog isattached by a covalent amide bond to the N-terminus of the peptide. Inanother embodiment, the metal binding moiety of the peptide analog iscovalently attached by a covalent amide bond to the C-terminus of thepeptide. In another embodiment, the metal binding of the peptide analogis attached by a covalent bond to a side chain of an amino acid of thepeptide. In further embodiments, a cleavable moiety is covalently boundand positionally located between the metal binding moiety and thepeptide. In exemplary embodiments, the metal binding moiety is a his tagwith cleavable moiety of the formula His-His-His-His-His-His-Gly-Gly-Gly(SEQ ID NO: 6), wherein the moiety is bound to either the N-terminus, orto the C-terminus, or to a side chain of an amino acid of the peptide.In a further embodiment, the metal binding moiety is a moiety of formula(Z_(y)His_(w))_(p) (SEQ ID NO: 50), wherein Z is an amino acid residueother than histidine, y is an integer from 0-6, w is an integer from1-6, and p is an integer from 1-6, and is bound to a cleavable moiety.In another embodiment, the metal binding moiety is nitrilotriacetic acidand is bound to a cleavable moiety, e.g., Gly₃, and the peptide. Inanother embodiment, the metal binding moiety is iminodiacetic acid andis bound to a cleavable moiety, e.g., Gly₃, and the peptide.

In certain embodiments, if peptide is GLP, A is attached to the peptideat a position other than the amino terminus.

Other chelating groups include1,4,7,10-tetraaza-cyclododecane-N,N′,N″-triacetic acid;1,4,7-tris(carboxymethyl)-10-(2′-hydroxypropyl)-1,4,7,10-tetraazocyclodecane,1,4,7-triazacyclonane-N,N′,N″-triacetic acid; and1,4,8,11-tetraazacyclotetra-decane-N,N′,N″,N′″-tetra acetic acid;diethylenetriamine-pentaacetic acid (DTPA);triethylenetetraamine-hexaacetic acid; ethylenediamine-tetraacetic acid(EDTA); EGTA; 1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid butpreferably N-(hydroxyethyl)ethylenediaminetriacetic acid;nitrilotriacetic acid (NTA); andethylene-bis(oxyethylene-nitrilo)tetraacetic acid, histidine, cysteine,oligoaspartic acid, oligoglutamic acid, S-acetyl mercaptoacetate andmeractoacetyltriglycine.

3. Cleavable Moiety

The present disclosure provides cleavable moieties that serve as linkersbetween the biologically active peptide and the binding moiety. Thecleavable moiety may include an amino acid sequence that can serve as asubstrate for a protease, usually an extracellular protease. In oneembodiment, the binding moiety is attached to the peptide through apolyglycine cleavable moiety, such as Gly-Gly-Gly. In anotherembodiment, the binding moiety comprises one or more cysteine residuescapable of forming a disulfide bond with corresponding cysteine residuesincorporated into the polymeric carrier, which can be cleaved by actionof a reducing agent. In such embodiments, cleavage of the cleavablemoiety in the body releases the peptide from the polymeric carrier. Thecleavable moiety may be (Gly)_(x) groups (SEQ ID NO: 58) and include,without limitation, Gly₂, Gly₃, Gly₄ (SEQ ID NO: 63), Gly₅ (SEQ ID NO:64) and Gly₆ (SEQ ID NO: 65). The cleavable moiety may also be (Ala)_(x)groups (SEQ ID NO: 59) and include without limitation Ala₂, Ala₃, Ala₄(SEQ ID NO: 66), Ala₅ (SEQ ID NO: 67) and Ala₆ (SEQ ID NO: 68). Thecleavable moiety may also be (Lys)_(x) groups (SEQ ID NO: 60) andinclude without limitation Lys₂, Lys₃/Lys 4 (SEQ ID NO: 69), Lys₅ (SEQID NO: 70) and Lys₆ (SEQ ID NO: 71). The cleavable moiety may also be(Arg)_(x) groups (SEQ ID NO: 61) and include without limitation Arg₂,Arg₃, Arg₄ (SEQ ID NO: 72), Arg₅ (SEQ ID NO: 73) and Arg₆ (SEQ ID NO:74). The cleavable moiety may also be (Ala-Arg)_(n) groups (SEQ ID NO:62), where n is between 1-3. The cleavable moiety may also be a moietyof formula (N)_(q)-Arg, wherein N is any amino acid and q is 0 or 1. Thecleavable moiety may also be a moiety of formula Arg-(N)_(q), wherein Nis any amino acid and q is 0 or 1. The cleavable moiety may also be amoiety of formula Lys-(N)_(q), wherein N is any amino acid and q is 0or 1. The cleavable moiety may also be a sequence of two amino acids inwhich one is Arg or Lys. Alternatively, the cleavable moiety may be anyone from a group consisting of

(SEQ ID NO: 7) Ile-His-Pro-Phe-His-Leu-Val-Ile-His-Thr; (SEQ ID NO: 8)Leu-Ala-Gln-Ala-Val-Arg-Ser-Ser-Ser-Arg; (SEQ ID NO: 9)Glu-Arg-Nle-Phe-Leu-Ser-Phe-Pro; (SEQ ID NO: 10)Ser-Gln-Asn-Tyr-Pro-Ile-Val-Gln; (SEQ ID NO: 11)Arg-Gly-Val-Val-Asn-Ala-Ser-Ser-Arg-Leu-Ala; (SEQ ID NO: 12)Glu-Val-Asn-Leu-Asp-Ala-Phe-Lys; (SEQ ID NO: 13)Glu-Val-Asn-Leu-Asp-Ala-Glu-Phe-Lys; (SEQ ID NO: 14)Glu-Val-Lys-Val-Asp-Ala-Glu-Phe-Lys; (SEQ ID NO: 15)His-Gln-Lys-Leu-Val-Phe-Phe-Ala-Lys; (SEQ ID NO: 16)Lys-Thr-Glu-Glu-Ile-Ser-Glu-Val-Asn-Leu-Asp- Ala-Glu-Phe;(SEQ ID NO: 17) Glu-Val-His-His-Gln-Lys-Leu-Val-Phe-Phe-Ala-Glu;(SEQ ID NO: 18) Pro-Gln-Gly-Leu-Glu; (SEQ ID NO: 19)Arg-Pro-Lys-Pro-Val-Glu-Nva-Trp-Arg-Lys; (SEQ ID NO: 20)Arg-Pro-Lys-Pro-Tyr-Ala-Nva-Trp-Met-Lys; (SEQ ID NO: 21)Pro-Leu-Ala-Tyr-Trp-Ala-Arg; (SEQ ID NO: 22)Arg-Pro-Leu-Ala-Leu-Trp-Arg-Ser; (SEQ ID NO: 23)Arg-Pro-Lys-Pro-Leu-Ala-Nva-Trp-Lys; (SEQ ID NO: 24)Pro-Tyr-Ala-Tyr-Trp-Met-Arg; (SEQ ID NO: 25)Pro-Leu-Gly-Met-Trp-Ser-Arg; (SEQ ID NO: 26)Pro-Leu-Ala-Leu-Trp-Ala-Arg; (SEQ ID NO: 27)Pro-Leu-Gly-Leu-Trp-Ala-D-Arg; (SEQ ID NO: 28) Asp-Glu-Val-Asp;(SEQ ID NO: 29) Asp-Met-Gln-Asp; (SEQ ID NO: 30) Leu-Glu-Val-Asp;(SEQ ID NO: 31) Val-Glu-Ile-Asp; (SEQ ID NO: 32) Ile-Glu-Thr-Asp; and(SEQ ID NO: 33) Leu-Glu-His-Asp.

II. Polymeric Carrier

The polymeric carrier of the present invention include polymers andco-polymers of linear or branched structure or conjugates thereof,micelles, emulsions, colloids and solid surfaces, where the polymers mayin addition self-organize in supramolecular structures including atleast two polymers. The copolymers include as one of the main polymericelements a backbone core polymer that contains a hydrophobic bindinggroup or a metal binding group and, in certain embodiments, protectiveside chains, such as PEG or mPEG.

The backbone can be a linear polymer, such as a polyamino acid; e.g., ahomopolymer or a nucleic acid, or a branched polymer, such as acarbohydrate. In one example, a polymeric carrier composition of thepresent invention comprises the backbone linear homopolyamino acid corewith a degree of polymerization in the range of 2-10,000 to whichindependently and covalently linked are polyglycol protective sidechains, and chelating groups, where said chains and chelating groups areindependently linked to the backbone core polymer. In another example,the degree of polymerization of the backbone core is in the range of100-1,000. In still another example, the degree of polymerization is inthe range of 100 to 300. Examples of polymeric backbone cores includecarboxylated or carboxymethylated linear poly-1-lysine (PL) orpoly-D-lysine, carboxylated or carboxymethylatedpoly-alpha,beta-(2-aminoethyl)-D,L-aspartamide; poly-aspartic acid,poly-glutamic acid, copolymers of histidine with positively ornegatively charged aminoacids, carboxylated polyethyleneimines, i.e.,polyethylene imines reacted with derivatives of carbonic acids. Inpreferred embodiments, the backbone linear core comprises poly-lysine.

In another embodiment, the polymeric carrier further comprisesprotective side chains. In one embodiment, the protective side chaincomprises polyethylene glycol (PEG). In a further embodiment, theprotective side chain comprises alkoxy polyethylene glycol. In a furtherembodiment, the protective side chain comprises methoxy polyethyleneglycol (MPEG). The protective side chains of the embodiments will have amass of between 200 and 60,000 Daltons independent of the polymeric coreweight, preferably a mass of between 1000 and 40,000 Daltons, and morepreferably between 2,000 and 20,000 Daltons.

The metal binding domains of the polymeric carrier may includepolycarboxylic acids containing nitrogen where at least one ofcarboxylic groups may be utilized for covalent linking of the chelate tothe carrier backbone polymer component of the composition of theinvention. The addition of said metal ions to chelates included in thepolymeric carrier compositions of the invention either at roomtemperature or at elevated temperatures results in the formation ofcoordinate complexes (metal-chelates). These metal-chelate complexesbind to the metal binding domain of peptide, added either in a purifiedstate or in the presence of bulk protein or blood plasma proteins, withthe formation of peptide complex compositions containing coordinatecomplexes formed between the metal-chelate of the polymeric carrier andthe peptides. The amino acid sequence of the peptides of the inventionmay include one or more histidines or cysteines which increase thestability of the complex formed between the peptide and polymericcarrier metal-chelate complexes.

Hydrophobic binding moieties attached to the carrier can include analkyl group. In a further embodiment, the alkyl group comprises a linearor branched alkyl group. In a further embodiment, the alkyl group can beat least partially saturated. In a further embodiment, the alkyl groupcomprises an ethyl or propyl group. In a further embodiment, the alkylgroup is a butyl, pentyl, or hexyl group. In a further embodiment, thealkyl group is CH₃(CH₂)_(n)CH₂—, CH₃(CH₂)_(n)CH₂NH—, CH₃(CH₂)_(n)CO—,CH₃(CH₂)_(n)CH₂O—, CH₃(CH₂)_(n)CH₂S—, —OC(CH₂)_(n)CH₂—,—OC(CH₂)_(n)CH₂NH —, —OC(CH₂)_(n)CO—, —OC(CH₂)_(n)CH₂O—,—OC(CH₂)_(n)CH₂S —, —HNC(CH₂)_(n)CH₂—, —HNC(CH₂)_(n)CH₂—,—HNC(CH₂)_(n)CH₂NH —, —HNC(CH₂)_(n)CO—, —HNC(CH₂)_(n)CH₂O —,—HNC(CH₂)_(n)CH₂S—, —OCH₂(CH₂)_(n)CH₂—, —OCH₂(CH₂)_(n)CH₂NH —,—OCH₂(CH₂)_(n)CO—, —OCH₂(CH₂)_(n)CH₂O—, or —OCH₂(CH₂)_(n)CH₂S— group,wherein “n” is 4-34, inclusive. In a further embodiment the present thehydrophobic chain is —(CH₂)₄NHCO(CH₂)_(n)OC-A-OR₃,—(CH₂)₄NHCO(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, —CH₂OOC(CH₂)_(n)OC-A-OR₃,—CH₂OOC(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, —CH(CH₃)OOC(CH₂)_(n)OC-A-OR₃,CH(CH₃)OOC(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, CH₂COOC(CH₂)_(n)CO-A-OR₃,—CH₂COOC(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃,—CH₂CONH(CH₂)_(n)NHCOCH₂CH₂-A-OR₃,—CH₂CONH(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, —(CH₂)₂COOC(CH₂)_(n)CO-A-OR₃,—(CH₂)₂COOC(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃,(CH₂)₂CONH(CH₂)_(n)NHCOCH₂CH₂-A-OR₃,—(CH₂)₂CONH(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, —(C₆H₄)OCO(CH₂)_(n)CO-A-OR₃,and —(C₆H₄)OCO(CH₂)_(n)NHCO(CH₂)_(y)CO-A-OR₃, wherein n is 2-22; y is2-6; R₃ is H, (CH₂)_(p)CH₃ or (CH₂)_(p)COOH, wherein p is 0-7; and A is[OCH₂CH₂]_(x) or [OCHCH₃CH₂]_(X), wherein x is 17-250, or variouscombinations of [OCH₂CH₂] or [OCHCH₃CH₂] with a total of 17-250 units.In another embodiment, the hydrophobic group comprises an aromatic ringcompound. In a further embodiment, the aromatic ring is phenyl. In afurther embodiment, the aromatic ring is naphthyl. In a furtherembodiment, the aromatic ring compound is cholesterol. In a furtherembodiment, the aromatic ring compound is fluorescien and the carboxylgroup in fluorescien will act as orienting molecule.

The percent load capacity of the polymeric carrier for the peptideanalog can vary, depending on the respective compositions of the carrierand the peptide analog. In one embodiment, the peptide analogs of thepresent invention are complexed with the polymeric carrier compounds bydissolving or suspending one hundred mg of the polymeric carrier in anappropriate solvent; e.g., phosphate buffered saline, saline, acetatebuffer, water or other appropriate solvent known in the art to becompatible for parenteral drug administration, and mixing with 1-200 mgof peptide analog of the present invention in a final unit volume of 100μl to 1 ml until the peptide analog is bound to the carrier. Theresulting formulation can be lyophilized for later reconstitution inappropriate volume for administration to a patient. The formulation canalso be filter sterilized prior to lyophilization or prior toadministration to a patient. Alternatively the carrier can be filtersterilized by passing through a filter (0.10 μm to 0.22 μm filter) priorto mixing with a peptide analog of the present invention that has beensterilized in similar manner.

III. Peptide Formulations

For administration to patients, the peptide complex compositions areprovided in a pharmaceutically acceptable form. In one embodiment, thevasopressin analog peptide or its salt is provided in a pharmaceuticallyacceptable vehicle as a preparation that is sterile-filtered, e.g.,through a 0.22 μm filter, and is substantially pyrogen-free. Desirably,the vasopressin analog peptide to be formulated migrates as a single orindividualized peak on HPLC, exhibits uniform and authentic amino acidcomposition and sequence upon analysis thereof, and otherwise meetsstandards set by the various national bodies which regulate quality ofpharmaceutical products. The analogs with alkyl group of 6-36 carbonunits can form micelle and can be administered in a suitable solvent.Alternatively, the analogs with alkyl group of 6-36 carbon units can beincorporated into a carrier with hydrophobic core such as thosedescribed in U.S. patent application Ser. No. 11/613,183. Alternatively,the alkyl containing analogs may be incorporated into micelles orliposomes. The analogs with 2-6 histidine residue (SEQ ID NO: 51) can beincorporated into metal containing carriers such as those described inU.S. Pat. No. 7,138,105. These carriers will further prolong the bloodcirculation half-life of these analogs by preventing their rapidactivation which would be followed by rapid elimination from the blood.

For therapeutic use, the chosen vasopressin- or other peptide-analog isformulated with a carrier (such as those described in U.S. Pat. No.7,138,105 and U.S. application Ser. No. 11/613,183, herein incorporatedby reference) and/or other pharmaceutically acceptable diluents orexcipients that is appropriate for delivering the peptide by the chosenroute of administration. Other suitable pharmaceutically acceptablediluents or excipients are those used conventionally with peptide-baseddrugs. Reference may be made to Remington's Pharmaceutical Sciences”,17th Ed., Mack Publishing Company, Easton, Pa., 1985, for guidance ondrug formulations generally. In one embodiment of the invention, thecompounds are formulated for administration by infusion or by injection,e.g., sub-cutaneously, intramuscularly or intravenously, and areaccordingly utilized as aqueous solutions in sterile and pyrogen-freeform and optionally buffered to physiologically tolerable pH, e.g., aslightly acidic or physiological pH. Thus, the compounds may beadministered in a vehicle such as distilled water or, more desirably, insaline, phosphate buffered saline or 5% dextrose solution. Watersolubility of the vasopressin/or other peptides analogs, especiallythose with alkyl group, may be enhanced, if desired, by incorporating asolubility enhancer. The vasopressin/ or other peptide analogs of theinvention may also be formulated as a slow release implantation deviceto further extend the duration of action. Examples of such sustainedrelease formulations include composites of biocompatible polymers, suchas poly(lactic acid), poly(lactic-co-glycolic acid), methylcellulose,hyaluronic acid, collagen, and the like, preferably with covalentlyattached hydrophobic moiety or metal chelates. The structure, selectionand use of degradable polymers in drug polymeric carriers have beenreviewed in several publications, including, A. Domb et al., Polymersfor Advanced Technologies 3:279-292 (1992). Additional guidance inselecting and using polymers in pharmaceutical formulations can be foundin the text by M. Chasin and R. Langer (eds.), “Biodegradable Polymersas Drug Delivery Systems, Vol. 45 of “Drugs and the PharmaceuticalSciences,” M. Dekker, New York, 1990. Liposomes may also be used tofurther sustain the action of vasopressin analogs. Details concerninghow to use and make liposomal formulations of drugs of interest can befound in, among other places, U.S. Pat. No. 4,944,948; U.S. Pat. No.5,008,050; U.S. Pat. No. 4,921,706; U.S. Pat. No. 4,927,637; U.S. Pat.No. 4,452,747; U.S. Pat. No. 4,016,100; U.S. Pat. No. 4,311,712; U.S.Pat. No. 4,370,349; U.S. Pat. No. 4,372,949; U.S. Pat. No. 4,529,561;U.S. Pat. No. 5,009,956; U.S. Pat. No. 4,725,442; U.S. Pat. No.4,737,323; U.S. Pat. No. 4,920,016. In one embodiment of the invention,the package contains the vasopressin/or other peptide analog (similarlyaltered as vasopressin analogs) with or without additional carrier,diluent and excipients as an administration-ready formulation.Alternatively, and according to another embodiment of the invention, thepackage provides the vasopressin/ or peptide analog with or withoutcarrier in a form, such as a lyophilized form, suitable forreconstitution in a suitable diluent or excipients, such asphosphate-buffered saline. In one embodiment, the package is asterile-filled vial or ampoule containing an injectable solution whichcomprises an effective, active amount of vasopressin/or other peptideanalog dissolved in an aqueous vehicle. As an alternative to injectableformulations, the vasopressin/or other peptide analog may be formulatedfor administration by other routes. Oral dosage forms, such as tablets,capsules and the like, can be formulated in accordance with standardpharmaceutical practice.

IV. Methods of Use

The novel compositions disclosed herein can be selected for use inmethods of treatment of patients according to the combinations ofpeptide analogs and polymeric carriers provided and the underlyingdisease or physiologic condition of the patient and/or the moleculartarget and its location. The peptide analog compositions can beadministered by any suitable means or route, including parenteral,intrapulmonary, and intranasal, and, if desired, for local injection.Parenteral administration routes include intramuscular, intravenous,intraarterial, intraperitoneal, or subcutaneous administration.

The appropriate dosage of peptide analog will depend on the type ofdisease or condition to be treated, the severity and course of thedisease, the patient's clinical history and response to the peptideanalog, and the discretion of the attending physician. Peptide analogscan suitably be administered to the patient in a single dose, in divideddoses, or over a series of treatments. Also, the present inventioncontemplates mixtures of more than one peptide analog, as well as use incombination with other therapeutic agents.

In certain embodiments, the dosage of the subject compounds willgenerally be in the range of about 0.01 ng to about 1 g per kg bodyweight, specifically in the range of about 1 ng to about 0.1 g per kg,and more specifically in the range of about 100 ng to about 10 mg perkg.

The peptide analog and polymeric carrier compositions will beformulated, dosed, and administered in a fashion consistent with goodmedical practice. Factors for consideration in this context include theparticular disorder being treated, the particular mammal being treated,the clinical condition of the individual patient, the cause of thedisorder, the site of delivery of the peptide, the method ofadministration, the scheduling of administration, and other factorsknown to medical practitioners. The “therapeutically effective amount”of a peptide composition and polymeric carrier complex to beadministered will be governed by such considerations, and is the minimumamount necessary to prevent, ameliorate, or treat a disease or disorder.

The precise time of administration and dosage of any particular compoundthat will yield the most effective treatment in a given patient willdepend upon the activity, pharmacokinetics, and bioavailability of aparticular compound, physiological condition of the patient (includingage, sex, disease type and stage, general physical condition,responsiveness to a given dosage and type of medication), route ofadministration, and the like. The guidelines presented herein may beused to optimize the treatment, e.g., determining the optimum timeand/or amount of administration, which will require no more than routineexperimentation or will consist of monitoring the subject and adjustingthe dosage and/or timing. An effective dose or amount, and any possibleaffects on the timing of administration of the dose, may need to beidentified for any particular composition of the present invention.Dosages for the compounds of the present invention may be readilydetermined by techniques known to those of skill in the art. In oneembodiment, the effective dose may be determined by routine experimentusing one or more groups of animals (preferably at least 5 animals pergroup), or in human trials if appropriate. In another embodiment, theeffectiveness of the composition and method of treatment or preventionmay be assessed by administering the peptide analog and assessing theeffect of the administration by measuring one or more indices associatedwith the disease or condition of interest, and comparing thepost-treatment values of these indices to the values of the same indicesprior to treatment. For repeated administrations over several days orlonger, depending on the condition, the treatment is sustained until adesired suppression of disease symptoms occurs. Accordingly, the methodof treatment embodiments can include obtaining single or sequentialblood or other body fluid samples from a patient after administration ofthe composition and quantitatively assaying for the free peptide by useof assays known in the art; e.g., HPCL, bioassay, mass spectronomy andthe like. Resulting values can be compared to threshold values known inthe art to correspond to therapeutically-effective concentrations; e.g.,area under the curve (AUC), half-life, Cmax, and other pharmacokineticparameters known in the art.

Generally, alleviation or treatment of a disease or disorder involvesthe lessening of one or more symptoms or medical problems associatedwith the disease or disorder. Thus, one embodiment of the inventionrelates to a method of use of novel long-acting vasopressin peptideanalogs in sustained release polymeric carrier complexes administered toa patient to increase blood perfusion to various organs in hypovolemicand hypotensive condition and/or increase the level of factor VIII andplasminogen activator in the blood. Exemplary disease or physiologicconditions in which the methods of treatment using the vasopressinpeptide analogs of the present disclosure would have utility include,but are not limited to, hypovolemia, splanchnic vasodilation, systemicvasodilation, hypotension, esophageal variceal hemorrhage, hepatorenalsyndrome (HRS), type 1 HRS, type 2 HRS, sepsis, liver cirrhosis, portalvein hypertension, esophageal varices, paracentesis-induced circulatorydysfunction, arterial hypotension induced by byproducts of bacteria,anesthesia-associated hypotension, cardiac arrest, and post-partumhemorrhage. Under these conditions a long acting vasoconstrictor such asthe vasopressin analogs of the invention will be beneficial for thesepatients.

In another embodiment, the invention related to a method of use of novelGLP peptide analog compositions. In preferred embodiments, thecompositions are GLP-1 analogs with insulinotropic activity. The term“insulinotropic activity” relates to the ability of a substance tostimulate, or cause the stimulation of, the synthesis or expression ofthe hormone insulin. Thus, one embodiment of the invention relates toadministration of novel long-acting GLP-1 analogs in sustained releasepolymeric carrier complexes to a patient to increase insulin levels in apatient, with concommitant reductions in circulating glucose levels. Inone embodiment, the insulinotropic property of the GLP-1 analogs may bedetermined by administering the analog to a patient and monitoring therelease of immunoreactive insulin (IRI) into the circulatory system. Thepresence of IRI is detected through the use of a radioimmunoassay whichcan specifically detect insulin or by other methods known in the art. Inanother embodiment, the therapeutic efficacy of the GLP-1 analogs can bedetermined by monitoring effects on circulating glycemic variables onsingle, repeated, or post-prandial or post-glucose-load blood samplesand comparing the concentrations to values known in the art tocorrespond to normal glucose tolerance, impaired glucose tolerance, ordiabetes-associated values for fasting and postload glucose and insulin,glycosylated hemoglobin (HbA1c), lipids, as well as insulin resistanceparameters. In another embodiment, the invention related to a method ofuse of compositions of GLP-2 analogs having therapeutic utility in thetreatment of diseases of the gastrointestinal tract. In particular, theGLP-2 analogs can act as trophic agents to enhance and maintain thefunctioning of the gastrointestinal tract and to promote growth ofintestinal tissue. The methods and formulations of the present inventionpreferably provide about 0.1 to about 50 mg/ml of GLP-2 or abiologically active fragment thereof, preferably about 5 to about 40mg/ml, more preferably about 7 to about 30 mg/ml, even more preferablyabout 10 to about 20 mg/ml, and most preferably about 20 mg/ml.

The invention may be better understood with reference to the followingexamples. These examples are intended to be representative of specificembodiments of the invention, and are not intended as limiting the scopeof the invention as any peptide can be altered similarly as alterationmade to vasopressin and the similar slow activation is expected to beobserved on the presence of serum. Occasionally modified peptidedepending on the peptide may be active after modification such as GLP-1modification proposed here (Example 9; FIGS. 20 and 21).

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention.

EXAMPLES Example 1

The synthesis ofCH₃(CH₂)₁₀CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂ (SEQ IDNO: 34) (also referred to as C12TerA which is a lysine vasopressinanalog) with disulfide bonds between the two cysteine residues (Cys4 andCys9) was done by Anaspec, San Jose, Calif., according to the inventor'sspecification. The known standard amino acids in the formula above arerepresented by three letter abbreviations know to those skilled in theart (See FIG. 2 for complete chemical formula). In this lysinevasopressin analog, lauric acid was attached to the N-terminalaminogroup of the peptide via amide bond formed between the carboxylgroup of lauric acid and the amino group of glycine residue of thepeptide. The known standard amino acids in the formula above arerepresented by three letter abbreviations known to those skilled in theart. At the end of the synthesis the determined molecular mass was foundto be 1409.5 Da corresponding to protonated peptide or the molecular ionpeak on mass spectroscopic analysis. This was consistent with thetheoretical molecular mass of 1410.4 Da when protonated. This peptidewas a white powder with limited solubility in water and was easilyobtained at purity of greater than 90% in this case. This peptide canform micelle in water (see FIG. 10), which protects the peptide fromrapid activation into vasopressin (see Table 1) and eventualinactivation. As can be seen in FIGS. 11 and 12, after incubation inserum for 2 hours vasopressin analog (C12TerA) was able to inducecalcium influx in human umbilical endothelial cell culture indicatingthe presence of biological activity. Addition of alkyl group (C12) tothe peptide gives it a longer biological activity than the nativevasopressin (lysine vasopressin or arginine vasopressin) or the otherlong acting analog such as terlipressin (see FIG. 1 and Table 1). Inaddition to forming micelle, this vasopressin analog can be loaded (seeFIGS. 17 and 18) into a polymeric drug carriers containing hydrophobicgroup such as that described in U.S. patent application Ser. No.11/613,183, which is hereby incorporated by reference.

Example 2

The synthesis ofCH₃(CH₂)₁₀CO—OHC(CH₃)CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 35) (also referred to as C12TerE) with disulfide bondsbetween the two cysteine residues (Cys4 and Cys9) was done by custompeptide supplier Anaspec, San Jose, Calif., according to the inventor'sspecification. The known standard amino acids in the formula above arerepresented by three letter abbreviations know to those skilled in theart (see FIG. 3 for complete chemical formula). In this structure the 12carbon alkyl group was attached to the hydroxyl group of lactate whichwas attached to the amino terminus of the peptide via amide bond throughits carboxyl group. This provides a hydrolysable ester bond which isbelieved to be less stable than amide bond and will facilitate theremoval of the 12 carbon fatty acid. At the end of the synthesis thedetermined molecular mass was found to be 1481.6 Da, corresponding toprotonated peptide or the molecular ion peak on mass spectroscopicanalysis. This is consistent with the theoretical molecular mass of1482.5 Da when protonated. This peptide was off-white powder withlimited solubility in water and was easily obtained at purity of greaterthan 90% in this case. This peptide can form micelle (FIG. 10) in water,which protects the peptide from rapid activation into lysine vasopressin(see Table 1) and eventual inactivation.

Example 3

The synthesis ofCH₃(CH₂)₆CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂ (SEQ IDNO: 36) (also referred to as C8TerA) with disulfide bonds between thetwo cysteine residues was done by custom peptide supplier Anaspec, SanJose, Calif., according to the inventor's specification. The knownstandard amino acids in the formula above are represented by threeletter abbreviation know to those skilled in the art (see FIG. 4 forcomplete chemical formula). In this vasopressin analog, octanoic acidwas attached to the N-terminal aminogroup of the peptide via amide bondformed between the carboxyl group of octanoic acid and the amino groupof glycine. At the end of the synthesis the determined molecular masswas found to be 1354 Da corresponding to protonated peptide or themolecular ion peak on mass spectroscopic analysis. This was consistentwith the theoretical molecular mass of 1354.4 Da when protonated. Thispeptide was water soluble, was a white powder, and was easily obtainedat purity of greater than 90% in this case.

Example 4

The synthesis ofCH₃(CH₂)₆CO—OHC(CH₃)CO-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 37) (also referred to as C8TerE) with disulfide bondsbetween the two cysteine residues was done by Anaspec, San Jose, Calif.,according to the inventor's specification. The known standard aminoacids in the formula above are represented by three letter abbreviationsknow to those skilled in the art (see FIG. 5 for complete chemicalformula). In this vasopressin analog, octanoic acid was attached to thehydroxyl group of lactic acid via ester bond and the carboxyl group oflactic acid was attached to the amino group of glycine via an amidebond. This provides an in vivo hydrolysable ester bond which is believedto be less stable than an amide bond and facilitates the removal of the8 carbon fatty acid. At the end of the synthesis the determinedmolecular mass was found to be 1425.7 Da, corresponding to protonatedpeptide or the molecular ion peak on mass spectroscopic analysis. Thiswas consistent with the theoretical molecular mass of 1426.5 Da whenprotonated. This peptide was water soluble, was a white powder and waseasily obtained at purity of greater than 90% in this case.

Example 5

The synthesis ofHis-His-His-His-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂(SEQ ID NO: 38) (also referred to as His6Ter (“His6” disclosed as SEQ IDNO: 52)) with disulfide bonds between the two cysteine residues was doneby Anaspec, San Jose, Calif., according to the inventor's specification.The known standard amino acids in the formula above are represented bythree letter abbreviations known to those skilled in the art (see FIG. 7for complete chemical formula). In this vasopressin analog, sixhistidine residues (SEQ ID NO: 52) were attached to the amino group ofglycine via amide bond. This provided a metal binding domain that can beused to attach this vasopressin analog to a protective carriercontaining metal chelate. Examples of metal chelate covalently linked topolymeric carrier include, but not limited to, DTPA-Zn²⁺, NTA-Zn²⁺,DTPA-Ni²⁺, NTA-Zn²⁺. The attachment will provide a slow release of thislysine vasopressin analog after administration to a patient. Further,those molecules that are released will be activated by enzymes in thebody to effect conversion to vasopressin. At the end of the synthesisthe determined molecular mass was found to be 2051.1 Da corresponding toprotonated peptide or the molecular ion peak on mass spectroscopicanalysis. This is consistent with the theoretical molecular mass of2051.3 Da when protonated. This peptide was water soluble, was a whitepowder, and was easily obtained at purity of greater than 95% in thiscase.

Example 6

The synthesis ofHis-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH₂ (SEQ IDNO: 39) (also referred to as His3Ter) with disulfide bonds between thetwo cysteine residues was done by Anaspec, San Jose, Calif., accordingto the inventor's specification. The known standard amino acids in theformula above are represented by three letter abbreviations known tothose skilled in the art (see FIG. 8 for complete chemical formula). Inthis vasopressin analog, 3 histidine residues were attached to the aminogroup of the terminal glycine via an amide bond. This provided a metalbinding domain that can be used to attach this vasopressin analog to aprotective carrier containing metal chelate. Examples of metal chelatecovalently linked to polymeric carrier include, but are not limited toDTPA-Zn²⁺, NTA-Zn²⁺, DTPA-Ni²⁺, and NTA-Zn²⁺. Additional carriers withmetal chelate are disclosed in U.S. Pat. No. 7,138,105 B2, which isherein incorporated by reference. The attachment to a protective carrierwill provide a slow release of this vasopressin analog afteradministration to a patient. Further, those molecules that are releasedwill be activated by enzymes in the body to effect conversion tovasopressin. At the end of the synthesis the determined molecular masswas found to be 1639.1 Da, corresponding to protonated peptide or themolecular ion peak on mass spectroscopic analysis. This is consistentwith the theoretical molecular mass of 1639.8 Da when protonated. Thispeptide was water soluble, was a white powder, and was easily obtainedat purity of greater than 95% in this case.

Example 7

The synthesis ofHis-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH₂ (SEQ IDNO: 40) (referred to as His3Vas) with disulfide bonds between the twocysteine residues were done by custom peptide supplier Anaspec, SanJose, Calif., according to the inventor's specification. The knownstandard amino acids in the formula above are represented by threeletter abbreviations know to those skilled in the art (see FIG. 8 forcomplete chemical formula). In this arginine vasopressin analog, 6histidines (SEQ ID NO: 52) were attached to the N-terminal aminogroup ofthe peptide via an amide bond formed between the carboxyl group ofhistidine and the amino group of glycine. This provides a metal bindingdomain that can be used to attach this vasopressin analog to aprotective carrier containing metal chelate. Examples of metal chelatecovalently linked to polymeric carrier include, but are not limited toDTPA-Zn²⁺, NTA-Zn²⁺, DTPA-Ni²⁺, and NTA-Zn²⁺. Additional carriers withmetal chelate are disclosed in U.S. Pat. No. 7,138,105 B2 which isherein incorporated by reference. The attachment to the protectivecarrier will provide a slow release of this arginine vasopressin analogafter administration to a patient. Further, those that are released willbe activated by enzymes in the body to effect conversion to argininevasopressin. At the end of the synthesis the determined molecular masswas found to be 1668 Da corresponding to protonated peptide or themolecular ion peak on Mass spectroscopic analysis. This was consistentwith the theoretical molecular mass of 1667.9 Da when protonated. Thispeptide was water soluble, was a white powder, and was easily obtainedat purity of greater than 95% in this case.

Example 8

The synthesis ofHis-His-His-His-His-His-Gly-Gly-Gly-Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH₂(SEQ ID NO: 41) (referred to as His6Vas (“His6” disclosed as SEQ ID NO:52)) with disulfide bonds between the two cysteine residues was done bycustom peptide supplier Anaspec, San Jose, Calif., according to theinventor's specification. The known standard amino acids in the formulaabove are represented by three letter abbreviations know to thoseskilled in the art (see FIG. 9 for complete chemical formula. In thisvasopressin analog, 6 histidines (SEQ ID NO: 52) were attached to theN-terminal aminogroup of the peptide via an amide bond formed betweenthe carboxyl group of histidine and the amino group of glycine. Thisprovides a metal binding domain that can be used to attach thisvasopressin analog to a protective carrier containing metal chelate.Examples of metal chelate covalently linked to polymeric carrierinclude, but are not limited to DTPA-Zn²⁺, NTA-Zn²⁺, DTPA-Ni²⁺, andNTA-Zn²⁺. Additional carriers with metal chelate are disclosed in U.S.Pat. No. 7,138,105 B2, which is herein incorporated by reference. Theattachment to protective carrier will provide a slow release of thisarginine vasopressin analog after administration to a patient. Further,those that are released will be activated by enzymes in the body toeffect conversion to arginine vasopressin. At the end of the synthesisthe determined molecular mass was found to be 2080.5 Da corresponding toprotonated peptide or the molecular ion peak on mass spectroscopicanalysis. This is consistent with the theoretical molecular mass of2079.3 Da when protonated. This peptide was water soluble, was a whitepowder, and was easily obtained at purity of greater than 95% in thiscase.

Example 9

The synthesis of the GLP-1 analogs SEQ ID NO: 2, SEQ ID NO: 3, SEQ IDNO: 4, and SEQ ID NO: 5 additionally containing iminodiacetic acid (IDA)or nitrilotriacetic acid (NTA) at the C-terminal was done by Anaspec,San Jose, Calif., according to the inventor's specification andprocedures (the attachment is as shown in FIGS. 20 and 21, where thepeptide is GLP as in SEQ ID NO: 2). The synthesis was initiated byattachment of iminodiacetic acid or nitrilotriacetic acid derivative(N′,N′,bis(carboxymethyl)-lysine with blocked epsilon amino group) tothe Wang's resin followed by blocking of the remaining carboxyl groups.The syntheses yielded the following sequences:

(SEQ ID NO: 42)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-IDA; (SEQ ID NO: 43)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-IDA;(SEQ ID NO: 44)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-IDA;(SEQ ID NO: 45)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-Gly-IDA;(SEQ ID NO: 46)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-NTA; (SEQ ID NO: 47)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-NTA;(SEQ ID NO: 48)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-NTA; and(SEQ ID NO: 49)His-Ala-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile[[u]]-Ala-Trp-Leu-Val-Lys-Gly-Arg-Gly-Gly-Gly-NTA.

The first amino acid was attached to the secondary amino group ofiminodiacetic acid or the primary amino group (after de-blocking) ofN′,N′,bis(carboxymethyl)-lysine immobilized in the resin. This wasfollowed by sequential addition of amino acids shown above according tothe standard protocol known in the art. It should be noted that thisexample is not to limit the scope of the invention and that any GLPanalog can be processed in a similar manner. It is also understood thatin the present invention, the IDA and NTA can be attached to the R-groupof any amino acids of GLP-1, except in the first six amino acids(His-Ala-Glu-Gly-Thr-Phe-Thr-Ser (SEQ ID NO: 75)) and in the N-terminal.In one particular example glycine was attached first. The number ofglycines may vary from 0 to 3 before addition of arginine This wasfollowed by Arg, Gly, Lys and so on according to the above sequence. Atthe end of the synthesis the peptide was cleaved from the resin,deprotected, and purified. In this GLP-1 analog, iminodiacetic acid ornitrilotriacetic acid is at the C-terminal carboxyl group of thepeptide. This also facilitates purification of the peptides using metalaffinity column. More importantly, this provides additional metalbinding domain to GLP-1 that can be used to attach this GLP-1 or itsanalogs to a protective carrier containing metal chelate. Examples ofmetal chelate covalently linked to polymeric carrier include, but arenot limited to DTPA-Zn²⁺, NTA-Zn²⁺, DTPA-Ni²⁺, and NTA-Zn²⁺. Additionalcarriers with metal chelate are disclosed in U.S. Pat. No. 7,138,105 B2,which is herein incorporated by reference. The attachment to protectivecarrier provides a slow release of this GLP-1 or its analogs afteradministration to a patient.

Example 10 Testing of Biological Activity of Various Vasopressin Analogs

Ca-influx after vasopressin analog stimulation of human umbilical chordartery endothelial cells (HUAEC) was used to test the biologicalactivity of the various vasopressin analogs. The material used were: 75cm² tissue culture flasks, BD Bioscience, Bedford Mass. (cataloguenumber 137787) with 0.2 μm vented blue plug seal caps (catalogue number353136); human umbilical artery endothelial cells (HUAEC), Lonza,Walkersville, Md. (catalogue number CC-2520); EGM-2 fully supplementmedium, Lonza, Walkersville, Md. (catalogue number CC-3162); Fura-2 AM,Invitrogen/Molecular Probes, Carlsbad, Calif. (catalogue number F-1221)(Fura-2 AM is a high affinity, intracellular calcium indicator that isratiometric and UV light-excitable; the acetoxymethyl (AM) ester form isuseful for noninvasive intracellular loading as it is cell permeable.Once inside the cell the ester is clipped which renders the Fura-2molecule cell impermeable and therefore trapped inside.); terlipressinderivatives custom made by Anaspec, San Jose Calif., according toinventors specifications; pooled human serum, Sigma, St. Louis, Mo.(catalogue number H4522); phosphate buffered saline (PBS), FisherScientific, Fair Lawn, N.J. (catalogue number BP399-500); trypsin-EDTAsolution, 0.25%, Invitrogen/Gibco, Carlsbad, Calif. (catalogue number25200-072); heat inactivated fetal bovine serum (FBS), Invitrogen/Gibco,Carlsbad, Calif. (catalogue number 10438-026); black polystyrene 96 wellflat-bottom assay plates, Corning Inc., Corning, N.Y. (catalogue number3916); Chameleon plate multilabel detection reader, Hidex, Turku,Finland, distributed by Bioscan, Washington, D.C.; dimethyl sulfoxide(DMSO), Fisher Scientific, Fair Lawn, N.J. (catalogue number D-136-1).

The methods used for tissue or cell culture are as follows: a vial ofHUAEC (>0.5×10⁶ cells) was thawed and seeded in two 75 cm² flasks with15 ml EGM-2 medium each. Cells were grown over night and medium waschanged. Media in the flasks were changed on a Monday, Wednesday, Fridayschedule. Cells were split at approximately 80% confluency (usingtrypsin). Media were removed and the flasks were washed with 10 ml1×PBS. The PBS was removed, 1.5 ml trypsin-EDTA solution was added andincubated for 5 min at 37° C. Three ml pf FBS added and the cells werecounted. The cells were centrifuged at 200×G for 5 min, resuspended inEGM-2 medium and distributed into new 75 cm2 flasks @ 3000-5000 cellsper cm2.

To prepare for the Ca2+-influx assay, cells were distributed into oneblack 96 well plate @ 105 cells/well. Cells were allowed to adhereovernight and the medium was then removed. Fifty μg Fura-2 was dissolvedin 50 μl DMSO and added to 10 ml PBS/2% FBS. The cells were stained with20 μl of 5 μg/ml Fura-2 in PBS/2% FBS for 2 h, then 180 EGM-2 mediumsupplemented with CaCl₂ and glucose was added (10 mM CaCl₂ and 11.1 mMglucose final concentrations).

To prepare analogs for testing, 50 uM terlipressin (or derivative) stocksolution in DMSO was prepared. Incubation of 30 ml of the drugs (500 nMfinal concentration) in 3 ml 100% human serum (NOT heat inactivated) for0, 1, 2, and 24 h was performed at 37° C. (placed on ice afterincubation).

To measure Ca-influx, Fura-2 fluorescence was measured for 4 repetitionsper well at 340 nm ex/510 nm em and 420 nm ex/510 nm em (4 measurementbefore and 16 after injection of drug. At t=12 sec, 20 μl ofterlipressin or derivative was injected as a 500 nM solution (or serum)for a final concentration of 50 nM per well. Fura-2 fluorescence wasmeasured for an additional 16 repetitions per well at 340 nm ex/510 nmem and 420 nm ex/510 nm em (4 measurements before and 16 after injectionof drug). The controls included injected human serum alone, andterlipressin or derivative dissolved in PBS as negative controls. Allmeasurements were done in hexuplicate.

Data analysis was done using Graphpad Prism version 5.0 software(Graphpad software Inc, San Diego, Calif.). Data were normalized bysubtracting the baseline readings (the average of the first 4repetitions of Fura-2 fluorescence measurement before the injection ofdrugs) from the readings after injection. The results of the experimentsare shown in FIGS. 11-18. FIGS. 12-16 show 20 repeats of Fura-2fluorescence as a function of time in seconds on the x-axis. The y-axisshows fluorescence intensity in relative fluorescence units [RFU]. Afterthe first 4 data time points, the drugs are injected into the tissueculture well and fluorescence measurement is continued for 48 moreseconds. Fura-2 fluorescence intensifies as intra-cellular Ca²⁺concentration rise in response to a stimulus

FIG. 11 shows the ability of terlipressin and other vasopressin analogto be activated by serum after 2-hour incubation in human serum. TheY-axis is relative fluorescence units in human umbilical chord cellsloaded with fura-2 in 96-well plate. The fluorescence is proportional tothe calcium in cells cytoplasm. Vasopressin causes calcium influx intothe cells cytoplasm causing an increase in fluorescence. Variousvasopressin analogs were incubated with human serum for 2 hours andapplied to cells in culture. Fluorescence were read every 3 seconds attime intervals for 1 minute as shown. After application, those samplesthat get activated by serum cause calcium influx and hence increase influorescence. In particular, the terlipressin analog C12TerA (labeled asC₁₂Amide) caused pronounced calcium influx, relative to unmodifiedterlipressin and C12TerE (labeled as C12 ester).

FIGS. 12-13 shows that terlipressin is only fully active when injectedin the presence of serum since, as being an analogue, a short sequenceof amino acids needs to be cut off to leave fully active vasopressin.This step is very fast or the enzyme performing this step is active onice as the addition of human serum increases terlipressin activitysignificantly without pre-incubation at 37° C. FIG. 12 shows that allanalogs of vasopressin are inactive in PBS. FIG. 13 shows thatterlipressin gets activated in serum quickly (into lysine vasopressin)and activity is seen immediately (at 0 hours) and losses activityimmediately afterwards. Terlipressin once activated into lysinevasopressin loses its activity quickly due to further degradation inserum. Because of endogenous growth factors contained in human serum,human serum by itself produces a measurable Ca-influx signal. Activityof the drugs therefore needs to exceed the human serum signal. TheC8TerA (C8Terlipressin amide), C12TerA (C12Terlipressin amide) andC12TerE (C8Terlipressin ester) which are the vasopressin analogs of thepresent invention gets activated in serum and remains active for up to 4hr. The longer acting analogs are those with amide bond (see FIGS.14-16).

FIG. 17 is a Scatchard plot showing the binding of C12TerA to polymericcarrier containing a hydrophobic group disclosed in U.S. patentapplication Ser. No. 11/613,183, which is hereby incorporated byreference. The carrier also referred to as PGC-HC18 or 20PLPEG555-C18 ismade up of polylysine of 15-30 kDa where 55% of the amino group iscovalently modified to contain 5 kDa methoxypolyethylene glycol attachedby through succinate linker and the remaining 45% of the amino group isamide bonded to stearic acid carboxyl group all disclosed in U.S. patentapplication Ser. No. 11/613,183. Two hundred fifty μl solutions ofcarrier (2.5 mg/tube) were mixed with 0.20, 0.15, 0.10, 0.075, 0.050,and 0.025 mg of C12TerA. Sample was made up to 150 μl PBS and incubatedovernight. The bound from 75 μl was eluted from Bio-spin-P30. The voidvolume containing loaded carrier was unloaded by filtration through 100kDa MWCO filter after addition of 75 μl acetonitrile, to release load.The filtrate containing bound C12TerA was quantified by HPLC. Acontrolled passed through the same filter in 50% acetonitrile was usedas a reference for the total C12TerA in each tube, allowing for thecalculation of Free C12TerA in the original incubation mixture. C12-TerAelutes at 2.4 minutes. A gradient of 25-99% acetonitrile from 1-6minutes at a flow rate of 1.5 ml/min was used. The column was Mercury MS20×4 mm; 2 μm; C12 from Phenomenex. Although the Scatchard plot is notcompletely linear, an average Kd of 1-5 μM can be estimated, indicatinga strong interaction of C12TerA with the carrier containing thehydrophobic group, which is sufficient to prolong the biologicalhalf-life of the C12TerA and delay its rapid activation and degradation.It should be noted that some C12TerA can form micelle and may be countedas bound due to the analytical techniques used.

The amount of C12TerA capable of being bound to a carrier was determinedby varying the amount of the analog in the presence of 10 mg/mlhydrophobic group containing carrier PGC-HC18 or 20PLPEG555-C18. Thecarrier presented in the graph contains 20 kDa polylysine in which 55%of the epsilon amino group of polylysine was derivatized with 5 kDamethoxyPEG and 40% was derivatized by stearic acid. As shown in FIG. 18,most of the C12TerA was bound to the carrier containing hydrophobicgroup, which would be sufficient to prolong the biological half-life ofthe C12TerA and delay its rapid activation and degradation whenadministered to a patient.

Table 1 summarizes the results of the experiments in which the testsamples were exposed to serum for the indicated periods of time and thanassayed according to the methods described above. The results, expressedon a subjective scale as “−” for no detectable activity and “+” to “+++”for slight to high activity, respectively, indicate that terlipressinanalogs with a C8 or C12 alkyl group bonded to the amide of terlipressinwere able to protect the analog and maintain the biological activity ofthe activated terlipressin for at least 4 h. The results indicated thatthe addition of the hydrophobic group to terlipressin would be able toprolong the biological half-life of the C12TerA and delay its rapidactivation and degradation when administered to a patient.

TABLE 1 Activity of Various Vasopressin Analogs 0 h* 1 h 2 h 4 hTerlipressin +++ + − − C8-Amide- +++ +++ +++ +++ Terlipressin C12-Amide-+++ +++ +++ +++ terlipressin C12-Ester- +++ + − − terlipressin *Timepoints refer to the amount of time the sample was pre-incubated inpooled human serum at 37° C. After the preincubation time the sample wasplaced on ice. 0 h time point contains the same amount of serum as theother sample s. Samples without serum added showed no activity. Plainserum was used as negative control.

Example 11 Testing of Biological Activity of Vasopressin Analogs In Vivo

Using a rat ear model, a vasopressin analog with metal binding moiety ofthe present invention, His6Ter (“His6” disclosed as SEQ ID NO: 52), wasevaluated for it ability to maintain vasoconstriction for an extendedperiod of time. The analog was formulated at a 2% load in polymericcarrier containing 40PLPEG537-Zn-chelate. The peptide analog-polymericcomplex was injected subcutaneously into the back of one set of rats,while terlipressin alone was also injected similarly in another set ofrats. The ears were examined at baseline and at intervals up to 48 h.The ears of rats injected with the peptide analog in polymeric carrierhad longer pharmacologic efficacy than the known long acting analogterlipressin as evidenced by the finding that the His6Ter analog (“His6”disclosed as SEQ ID NO: 52) plus polymeric carrier-treated rats had earsthat remained pale at both the 6 and 24 h intervals, while theunformulated terlipressin-treated rats had ears that were pale at 6 hbut had returned to a baseline color with grossly apparent normal bloodflow at the 24 h interval.

Using the same model, the effects of delayed release ofbiologically-active lysine vasopressin from the peptide analog His6Ter(“His6” disclosed as SEQ ID NO: 52), with or without complexing inpolymeric carrier, was tested. In the experiment, terlipressin wasconjugated with a his tag metal binding moiety to result in the His6Terpeptide analog (“His6” disclosed as SEQ ID NO: 52). A portion of theHis6Ter analog (“His6” disclosed as SEQ ID NO: 52) was formulated at 2%loading in 40PLPEG537-Zn-chelate. The three test materials were injectedsubcutaneously into groups of rats and the ears were examined after 6and 24 h. Examination revealed that paling of ears was apparent for 24 hafter subcutaneous injection of His6Ter (“His6” disclosed as SEQ ID NO:52) formulated in 40PLPEG537-Zn-chelate while His6Ter (“His6” disclosedas SEQ ID NO: 52) alone and terlipressin alone show loss of palenessafter 6 hours. The results demonstrate that the peptide analog complexedwith polymeric carrier was able to result in sustained release ofbiologically-active lysine vasopressin for an extended period of timecompared to terlipressin alone and to the His6Ter peptide analog (“His6”disclosed as SEQ ID NO: 52) not formulated with polymeric carrier.

Although the foregoing invention has been described in some detail byway of illustration and example for the purposes of clarity ofunderstanding, one skilled in the art will easily ascertain that certainchanges and modifications may be practiced without departing from thespirit and scope of the appended claims.

EQUIVALENTS

Those skilled in the art will recognize, or be able to ascertain usingno more than routine experimentation, many equivalents to the specificembodiments of the invention described herein. Such equivalents areintended to be encompassed by the following claims.

1. A composition comprising a peptide analog having a general formula:A-(Cm)_(x)-(peptide), wherein: a. Cm is any one of alanine, lysine, andarginine; b. x is an integer from 2-6; c. A is an alkyl group with 6 to36 carbon units with a linker group selected from carbonyl and amino;and d. the A-(Cm)_(x)-(peptide) has lower biological activity in cellculture than the parent peptide in the absence of serum.
 2. Thecomposition of claim 1, further comprising a polymeric carrier with aplurality of hydrophobic groups of 8-36 carbons each, wherein group A ofthe peptide analog is non-covalently bound to the plurality ofhydrophobic groups of the polymeric carrier by hydrophobic interaction.3. The composition of claim 2, wherein the peptide is terlipressin or avariant thereof and A-(Cm)_(x)- is attached to the N terminus of thepeptide and the linker group is carbonyl.
 4. The composition in claim 2,wherein the peptide is selected from vasopressin, glucagon like peptide(GLP), leptin fragment, gastric inhibitory polypeptide (GIP), epidermalgrowth factor (EGF) receptor ligand, EGF, transforming growth factoralpha (TGF-alpha), gastrin/cholecystokinin receptor ligand, gastrin,cholecystokinin, auristatin, nisin, insulin, insulin-like growth factor,parathyroid hormone (PTH), atrial natriuretic factor, somatostatin,gonadotropin releasing hormone, leutinizing-hormone-releasing-hormone,vasoactive intestinal peptide (VIP), and derivatives thereof.
 5. Thecomposition of claim 2, wherein the peptide is 1 VIP or natriureticfactor and A-(Cm)_(x)- is attached to the C terminus of the peptide or aside chain.
 6. The composition of claim 2, wherein A is a linear alkyl.7. The composition of claim 3, wherein A is a linear alkyl.
 8. Thecomposition of claim 4, wherein A is a linear alkyl.
 9. The compositionof claim 5, wherein A is a linear alkyl.
 10. The composition of claim 2,wherein A is a branched alkyl.
 11. The composition of claim 3, wherein Ais a branched alkyl.
 12. The composition of claim 4, wherein A is abranched alkyl.
 13. The composition of claim 5, wherein A is a branchedalkyl.
 14. (canceled)
 15. The composition of claim 1, wherein thepeptide is selected from vasopressin, glucagon like peptide (GLP),leptin fragment, gastric inhibitory polypeptide (GIP), epidermal growthfactor (EGF) receptor ligand, EGF, transforming growth factor alpha(TGF-alpha), gastrin/cholecystokinin receptor ligand, gastrin,cholecystokinin, auristatin, nisin, insulin, insulin-like growth factor,parathyroid hormone (PTH), atrial natriuretic factor, somatostatin,gonadotropin releasing hormone, leutinizing-hormone-releasing-hormone,vasoactive intestinal peptide (VIP) and derivatives thereof.
 16. Thecomposition of claim 1, wherein the peptide is, terlipressin or avariant thereof and A-(Cm)_(x)- is not attached to the N terminus of thepeptide.
 17. The composition of claim 1, wherein A is a linear alkyl.18. The composition of claim 15, wherein A is a linear alkyl.
 19. Thecomposition of claim 16, wherein A is a linear alkyl.
 20. Thecomposition of claim 1, wherein A is a branched alkyl.
 21. Thecomposition of claim 15, wherein A is a branched alkyl.
 22. Thecomposition of claim 16, wherein A is a branched alkyl.
 23. A method ofmaking a peptide analog composition of claim 1 comprising: forming acovalent bond between a peptide in a resin and a group A- (reactivegroup) to form a resin-linked precursor to a composition comprising apeptide analog according to claim 1, where said peptide analog has lowerbiological activity in cell culture than the parent peptide in theabsence of serum.
 24. A method for treatment of hypovolemia, ascites,splanchnic vasodilation, systemic vasodilation, hypotension, esophagealvariceal hemorrhage, hepatorenal syndrome, or sepsis in a subject inneed of such treatment comprising administering to the subject apharmaceutical composition comprising a composition of claim 1 inpharmaceutically acceptable carrier wherein the peptide comprisessequence ID
 53. 25. A composition comprising (i) a peptide analog havinga general formula: A-(Cm)_(x)- (peptide) and (i) a polymeric carrierwith a plurality of hydrophobic groups of 8-36 carbons each, whereingroup A of the peptide analog is non-covalently bound to the pluralityof hydrophobic groups of the polymeric carrier by hydrophobicinteraction, wherein Cm is any one of glycine, alanine, lysine, andarginine; x is an integer from 1-6, and A is an alkyl group with 6 to 36carbon units.